Use of metal-accumulating plants for implementing chemical reactions

Abstract

A method of implementing organic synthesis reactions uses a composition containing a metal catalyst originating from a calcined plant. The plants can be from the Brassicaceae, Sapotaceae and Convolvulaceae family, and the metal catalyst contains metal in the M(II) form such as zinc, nickel, manganese, lead, cadmium, calcium, magnesium or copper. Examples of the organic synthesis reactions include halogenations, electrophilic reactions, cycloadditions, transesterification reactions and coupling reactions, among others.

Claims

1. A method for the implementation of an organic synthesis reaction, comprising: providing a composition comprising at least one metal catalyst containing a metal in the M(II) form, said metal originating from a calcined plant or calcined plant part, said composition having been acid treated, wherein said at least one metal in the M(II) form is selected from the group consisting of zinc (Zn), nickel (Ni), manganese (Mn), lead (Pb), cadmium (Cd), calcium (Ca), magnesium (Mg), and copper (Cu); and bringing the composition into contact with at least one chemical compound capable of reacting with said composition.

2. The method according to claim 1, wherein the organic synthesis reaction is selected from halogenations, electrophilic aromatic reactions in series, synthesis of 3,4-dihydropyrimidin-2(1H)-one or 3,4-dihydropyrimidin-2(1H)-thione, cycloaddition reactions, transesterification reactions, catalyst synthesis reactions for coupling or hydrogenation reactions after reduction of Ni(II) to Ni(0), synthesis of amino acid or oxime developers, and hydrolysis of sulphur-containing organic functions.

3. The method of claim 1, wherein said organic synthesis reaction is selected from halogenation of alcohols, electrophilic aromatic reactions in series, selected from substitutions or additions; catalyst synthesis reactions for coupling or hydrogenation reactions after reduction of Ni(II) to Ni(0), synthesis of 3,4-dihydropyrimidin-2(1H)-one or 3,4-dihydropyrimidin-2(1H)-thione, cycloaddition reactions, and synthesis of amino acid or oxime developers.

4. The method according to claim 1, wherein the organic synthesis reaction is the halogenation of primary, secondary or tertiary alcohols.

5. The method according to claim 1, wherein the organic synthesis reaction is an electrophilic reaction in series selected from electrophilic substitutions and additions.

6. The method according to claim 1, wherein the organic synthesis reaction is a Diels-Alder cycloaddition.

7. The method according to claim 1, wherein the organic synthesis reaction is a coupling reaction in the synthesis of diaryl compounds.

8. The method according to claim 1, wherein the organic synthesis reaction is the catalyzed hydrolysis of thiophosphates.

9. The method according to claim 1, wherein the metal is selected from zinc (Zn), nickel (Ni) and copper (Cu).

10. The method according to claim 1, wherein the metal is selected from zinc (Zn), nickel (Ni), manganese (Mn), lead (Pb) and cadmium (Cd).

11. The method according to claim 1, wherein the acid treatment is carried out by hydrochloric acid.

12. The method according to claim 1, wherein said plant is from the Brassicaceae family.

13. The method according to claim 1, wherein said plant is Anthyllis vulneraria, Thlaspi caerulescens or Arabidopsis hallerii and the metal is Zn.

14. The method according to claim 13, wherein the Zn concentration in the plant is from 2700 mg/kg to 43700 mg/kg of dry weight of plant or plant part.

15. The method according to claim 1, wherein said plant belongs to the Sapotaceae family and the metal is Ni.

16. The method according to claim 15, wherein the Ni concentration in the plant is from 1000 mg/kg to 36000 mg/kg of dry weight of plant or plant part.

17. The method according to claim 1, wherein said plant belongs to the Convolvulaceae family and the metal is Cu.

18. The method according to claim 17, wherein the Cu concentration in the plant is from 1000 mg/kg to 13700 mg/kg of dry weight of plant or plant part.

19. The method according to claim 1, wherein the composition is devoid of or contains only traces of chlorophyll.

20. The method according to claim 1, wherein said plant is Psychotria douarrei and the metal is Ni.

21. The method according to claim 1, wherein said plant is chosen from the genus Geissois or the genus Alyssum and the metal is Ni.

22. The method according to claim 1, wherein said plant is Bacopa monnieri and the metal is Cu.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 illustrates the general principles of spectrometry, in which light absorption is demonstrated by the number of photons (light intensity) that is lower when leaving the sample than when entering; and

(2) FIG. 2 schematically illustrates the catalyzed hydrolysis of thiophosphates utilizing catalysts prepared from Bacopa monnieri or Thlaspi caerulescens.

(3) FIG. 3 illustrates the selective precipitation of catalytic compounds as a function of pH.

(4) FIG. 4 illustrates the selective precipitation of catalytic compound as function of pH.

(5) FIG. 5 illustrates the preparation of different nickel salts from a single precursor: Psychotria douarrei.

EXAMPLES

Example 1

Preparation of a Composition Containing a Metal Catalyst the Metal of which is Zn

(6) 1.1: Obtaining the Crude Catalyst

(7) 30.03 g dehydrated and powdered leaves of Thlaspi caerulescens originating from the soil of the mine at Avnières are assayed by Escarré's method (zincon assay) in order to measure the level of zinc present in the dry matter (in the used and calcined samples: 420 mg or 2 mmoles: average level, depending on the site where the leaves are collected). The dry matter is then placed in 20 mL of 1N hydrochloric acid.

(8) Note: Dehydration is either calcining (approximately 300° C. for 2 hours: ash is then obtained), or heating at 100° C. under vacuum for 4 to 5 hours followed by grinding with a mortar). The mass of dry matter is then different (more organic products degraded and lost by calcining, see Table II below).

(9) TABLE-US-00002 TABLE II Results in ppm (ICP-MS) Mg Al Ca Fe Cu Zn Cd Pb dehydration 4394 2468 73827 3095 57 22501 1863 4653 calcining 11816 4726 90860 8738 99 61040 5498 12992
The above values are those obtained after treatment with 1N HCl and filtration.
The metals present in Table II are in the M(II) form except for the iron which is in the M(III) form.

(10) An alternative consists of treating the dry matter with 20 ml of 12N HCl.

(11) A fine and detailed analysis of the composition of the media was carried out by ICP-MS, the method using zincon (for the zinc) and pulse polarography.

(12) The results are all consistent and are repeated 3 times (expressed in ppm);

(13) Cl was assayed by the Mohr method (formation of the red Ag.sub.2CrO.sub.4 complex).

(14) C and N were assayed by the CHN dry method. The average values are summarized in Table III below:

(15) TABLE-US-00003 TABLE III Catalyst Mg Ca Fe Cu Zn Cd Pb Na K P Mn Ni Co Cl C N ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm % % With 1N HCl 11816 90860 8738 99 61040 5498 12992 23000 28000 9500 360 25 — ND ND ND With 12N HCl 13182 73827 27859 170 67744 5589 14946 — — — — — — 3441 0.14 0.021 ND: Not determined
The treatment with 12N HCl changes the composition, in particular enriches it with zinc(II) and iron (III) and relatively reduces the proportion of Ca.

(16) The solution is stirred for 1 hour, then sonicated for 2 hours. The medium is concentrated by heating the reaction medium. 1 to 2 mL of 12N HCl are added in order to allow satisfactory stifling of the medium.

(17) Note: if sonication is not required, concentration of the reaction medium must be provided, followed by the addition of 12N HCl.

(18) The solution is filtered on a frit having a porosity of 4. The solid residue is washed with 2 mL of 12N HCl. The filtrate must be perfectly clear. The pH is checked and optionally adjusted to a value less than 2 if necessary by the addition of 12N HCl. Rapid measurement of the zinc in solution by atomic absorption spectroscopy (Spectra Varian AA 220FS spectrometer) (Thlaspi caerulescens, un indicateur de la pollution d′un sol ? Une réflexion partagée entre étudiants et chercheurs autour d'un problème environnemental C. GRISON, J. ESCARRE, M. L. BERTHOMME, J. COUHET-GUICHOT, C. GRISON, F. HOSY, Actualité Chimique, 2010, 340, 27-32) makes it possible to check the recovered level of zinc (in the form of ZnCl.sub.2). Under the conditions described, on average 70% of the zinc initially introduced is recovered, in this case 1.4 mmoles.

(19) 1.2: Purification of the Catalyst Obtained in Example 1.1 with 12N HCl

(20) 1.2.1: Enrichment with Zn.sup.2+ and Fe.sup.3+

(21) Amberlyte IRA400 Resin (or Dowex 1)

(22) Before use, the resin must be left to swell for 24 hours in a 9N HCl solution. In order to separate 500 mg of product, 30 g of resin will be used. After swelling, the resin can be introduced into a column (9M HCl will be used in order to entrain the resin) at the ends of which cotton will be placed and, at the bottom, Fontainebleau sand on the cotton.

(23) The catalytic solution is then passed over the resin. Then the resin is rinsed for a first time with 150 mL of a 0.5N HCl solution at a rate of 3 mL per minute. The standard step of recovery of the zinc bound to the resin by passing a 0.005N HCl solution over it is not sufficient. The resin must be extracted from the column, then placed in a beaker containing 100 mL of a 0.005N HCl solution. The whole is placed under magnetic stirring and heated for 1 day at 50° C.

(24) In order to handle larger quantities of resin, better control the contact time and not have to prepare the column only to dismantle it before the re-extraction step, a crystallizer of a suitable size was used under magnetic stirring.

(25) The resin is left in contact with the catalytic solution under magnetic stirring for 10 minutes. This is sufficient to extract 95% of the zinc present in the catalytic solution: the latter is found bound to the resin complexed by chloride ions.

(26) The step of rinsing with 0.5M HCl which is intended to elute the iron is carried out under the same conditions: 10 minutes under magnetic stirring. The volume of the rinsing solution is adapted to the quantity of resin in order to recover it. Additional rinsing with 0.005M HCl makes it possible to remove the last traces of iron.

(27) results: complete mass balance at each step and mass of each element remaining on the resin (Table IV):

(28) TABLE-US-00004 TABLE IV Mass obtained in mg Mg Al Ca Fe Zn Cd Pb Cat. Sol 12M HCl 83.58 57.25 528.36 253.69 385.57 23.49 106.68 After Passing over 64.27 43.57 363.54 66.00 10.07 0.74 14.55 Resin Rinsing the resin with 10.87 5.58 68.94 67.35 2.05 0.09 5.83 0.5M HCl Rinsing the resin with 5.56 2.60 34.31 63.41 23.80 0.20 15.85 0.005M HCl Remaining on the resin 2.87 5.49 61.57 56.90 349.64 22.44 70.43 Yield % 3.4 9.5 11.6 22.4 90.6 95.5 66.0
Thorough washing with water (the resin is left in water for 12 hours under magnetic stirring) and filtration under vacuum make it possible to recover most of the zinc present initially (final mass: 319 mg, i.e. 83% yield). The analysis of the recovered residue is as follows:

(29) TABLE-US-00005 Results in ppm (ICP-MS) Mg Al Ca Fe Zn Cd Pb After washing 13973 430 20250 2610 704330 3170 11540 with water
The technique is simple and very effective; the solid obtained is kept in an oven at 90° C. and used in organic synthesis.

(30) Liquid-Liquid Extraction with Trioctylamine (TOA)

(31) A scale model of an industrial reactor was used for this method, making it possible to introduce and recover the different phases without having to dismantle the device. The organic phase which allows the extraction of the zinc is a 5% solution by mass of trioctylamine in toluene.

(32) For a catalytic solution prepared from 1 g of ash, we therefore used 1.7 g (2.1 mL) of trioctylamine in solution in 32.3 g (37.1 mL) of toluene.

(33) The catalytic solution obtained from 1 g of ash is brought into contact with the solution of trioctylamine in toluene. The whole is left for 12 hours under mechanical stirring in our reactor.

(34) The organic phase is then recovered and cleaned with 2N HCl for 2 minutes. This step is carried out in a separating funnel and with manual stifling.

(35) The cleaned organic phase is then returned to the reactor then 10 mL of a 0.05N HCl solution is added. It is left under mechanical stirring for half a day. The aqueous phase is recovered, then the process is repeated with 10 mL of 0.05N HCl solution. The two aqueous phases are combined, finally obtaining 20 mL of 0.05N HCl solution from which the zinc should have been recovered.

(36) results (Table V):

(37) TABLE-US-00006 TABLE V ICP-MS UM2 Mg Al Ca Fe Zn Cd Pb TOA extract ppm ppm ppm ppm ppm ppm ppm cg0 catalytic 11816 4726 90860 8738 61040 5498 12992 solution cg1 aq. ph. after 18670 7252 121300 274 27380 1633 20540 extr. cg2 aq. ph. after 2724 1171 18058 2492 22880 972 4930 2M HCl cg3 aq. ph. after 3520 3454 32020 72080 103320 723 4650 0.05M HCl concentration 30 73 35 824 169 13 35 factor %

(38) Selective Precipitations with NaF

(39) The catalytic solution is adjusted to pH=4 by the progressive addition of soda. Excess sodium fluoride is added. MgF.sub.2 et CaF.sub.2 precipitate. After centrifugation, the supernatant is adjusted to pH=10 by adding aqueous soda. The precipitate is centrifuged then analyzed. It is highly enriched with Zn(II). Treatment with concentrated HCl makes it possible to regenerate a catalytic solution enriched with ZnCl.sub.2. results (Table VI):

(40) TABLE-US-00007 TABLE VI ICP-MS UM2 Mg Al Ca Fe Zn Cd Pb ppm ppm ppm ppm ppm ppm ppm catalytic solution 16083 6323 102795 14943 72095 6116 19775 supernatant after centri. 3590 152 21050 416 19741 1672 806 precipitate pH > 10 15497 723 22380 2119 80113 7240 3580 supernatant at pH 10.8 199 62 18297 144 302 29 38 concentration factor % 96 11 21 14 111 118 18
selective precipitations as a function of the pH by the addition of NaOH 1M

(41) principle: to precipitate the different species with the pH

(42) See FIG. 3 results (Table VII):

(43) TABLE-US-00008 TABLE VII Mg Al Ca Fe Zn Cd Pb catalyst 13182 7404 73827 27859 67744 5589 14946 Precipitate 23467 14096 47298 53784 126524 10114 28483 pH < 10 supernatant 2518 990 52193 1071 529 59 392 Concentrate 178 190 64 193 186 180 190.57 Factor %

(44) The Fe.sup.3+ and Zn.sup.2+ coprecipitate: only the calcium shows a reduction in concentration while the concentrations of the other species increase.

(45) At pH 10, most of the zinc is in the form of Zn(OH).sub.2 and is found in the recovered precipitate. Improving the selectivity of the process can be envisaged by stopping at a lower pH: the concentration factor of the magnesium reduces and that of the zinc increases while the zinc yield drops.

(46) 1.2.2: Removal of the Fe.sup.3+

(47) The removal of Fe.sup.3+ is not imperative, but it can offer 2 advantages:

(48) a/ allowing clear precipitation of Zn(OH).sub.2. ((Fe(OH).sub.3 precipitates from pH 3 in colloidal form and entrains a portion of Zn.sup.2+).

(49) b/ facilitating AAS analyses (the precipitation of Fe(OH).sub.3 from pH=3 poses technical problems of concern to analysts)

(50) reducing the Fe3+ in the crude catalyst with sodium sulphite

(51) Principle: Reducing the Fe.sup.3+ to Fe.sup.2+ with SO.sub.2
SO.sub.3.sup.2−+2H.sub.3O.sup.+.fwdarw.SO.sub.2(aq)+3H.sub.2O
SO.sub.2(aq) 2Fe.sup.3++6H.sub.2O.fwdarw.2Fe.sup.2++SO.sub.4.sup.2−+4H.sub.3O.sup.+

(52) Protocol: 1 mL of 1M HCl is added to a 0.1M Na.sub.2SO.sub.3 solution in a 5 mL beaker. Sulphur dioxide in solution is then generated. This solution is then added to 2 mL of catalyst before concentration. The reduction is total (qualitative test with thiocyanate is negative), but the catalyst must be treated under an inert atmosphere.

(53) This reduction makes it possible to precipitate the Fe.sup.2+ quantitatively at pH 14; Zn(OH).sub.2 is then converted to ZnO.sub.2.sup.2−, which is water-soluble, unlike the iron, magnesium and calcium hydroxides in particular. However, the procedure must be carried out under an inert atmosphere and ZnCl.sub.2 is regenerated by treatment with 12N HCl. The medium has a high zinc concentration, but the dissolution of ZnO.sub.2.sup.2− is impaired because a colloid solution is obtained. The yield is of the order of 40% (Table VIII):

(54) TABLE-US-00009 TABLE VIII Catalyst Mg Al Ca Fe Zn Cd Pb Without SO.sub.2 treatment 11816 4726 90860 8738 61040 5498 12992 With SO.sub.2 treatment 2757 4564 58372 1128 89920 2324 12880

(55) By way of comparison and with the same aim of removing the Fe.sup.3+, liquid-liquid extraction tests with versatic acid and (2-ethylhexyl)phosphoric acid (DEHPA) were carried out according to the following protocol:

(56) A catalytic solution of 0.0005 mol/1 is prepared; the pH is adjusted to 2 by the addition of soda; 10 mg of NaCl is added in order to increase the ionic strength of the medium. The organic solution (versatic acid or DEHPA) is prepared at 1M in toluene. 15 mL of aqueous phase and 15 mL of organic phase are stirred for 30 minutes, then the mixture is centrifuged. The aqueous phase is isolated then concentrated and analyzed by ICP-MS. The extraction of iron to the organic phase is evident, but the zinc is also partially entrained (Table IX).

(57) TABLE-US-00010 TABLE IX Catalyst Mg Al Ca Fe Zn Cd Pb Originating from the 9766 556 99735 936 48800 3240 12880 aqueous phase after extraction of the Fe(III) with versatic acid Originating 10829 50 103445 350 31650 8810 890 from the aqueous phase after extraction of the Fe(III) with di(ethyl 2-hexyl)phosphoric acid

(58) 1.2.3: Removal of the Pb.sup.2+

(59) washing with acetone: a simple washing with acetone entrains Zn.sup.2+ and Fe.sup.3+ in solution and precipitates a significant portion of lead chloride (Table X).

(60) TABLE-US-00011 TABLE X Run g Mg Al Ca Fe Cu Zn Cd Pb ng/mL ppm ppm ppm ppm ppm ppm ppm ppm cat. Thlaspi 12M   5 g 14056 5121 87821 13852 240 95039 8307 16226 cat insoluble in acetone 2.25 g 12162 10445 109142 3998 109 2617 7832 38244 cat soluble in acetone 3.07 g 14403 289 70853 16032 319 186032 10754 221

Example 2

Assay of the Zinc in the Leaves of Plants, after Dehydration, by UV-Visible Spectrophotometry (Assay with Zincon, According to CEFE: Centre d'Écologie Fonctionnelle Et Évolutive, Hélène Frérot Et Bruno Buatois)

(61) Subject:

(62) Measurement of the zinc concentration in a plant sample after dissolving the metal in an acid, addition of a colorimetric agent, and analysis by UV-visible spectrophotometry of the intensity of the colouration which depends on the quantity of zinc in the sample.

(63) Definitions:

(64) Zincon=[alpha-(hydroxy-2 sulpho-5 phenylazo)benzylidene]hydrazino-2 benzoic acid, monosodium salt

(65) ##STR00003## C.sub.20H.sub.15N.sub.4NaO.sub.6S=462.41 g.Math.mol.sup.−1
Appearance: purple or dark reddish powder
Absorbance: >0.375 (around 490 nm)
Sulphated ash: 15-25%

(66) Zincon is a chelator of metals (Cu, Zn, Pb, Cd, Fe, Mn, Ni, Co, Al, etc.). The chelation of the zinc takes place at pH 8.5-9.5. At these pHs, the aqueous zincon solution is orange in colour, and changes to blue in the presence of zinc. At 606 nm, the absorbance values of a zinc solution containing zincon give the zinc concentration in the solution.

(67) Absorbance

(68) As illustrated in FIG. 1, the light absorption is demonstrated by a number of photons (light intensity) that is lower when leaving the sample than when entering.

(69) Is−I=−dI=k.c.I.dl which gives dI/I=−k.c.dl which is integrated according to

(70) ${\int }_{\mathrm{Io}}^I\frac{dI}{I}=-\mathrm{kc}{\int }_0^{I}dl$
which gives Ln(I/Io)=−k.c.L.

(71) The absorbance (A) is preferably defined according to A=log (I/Io)=−ε.c.L (Beer-Lambert's Law), where c is the molar absorption coefficient (in M.sup.−1.Math.cm.sup.−1). Sometimes the transmission T=I/Io is also used.

(72) It should be noted that 0<T<1 and 0<A< and that absorbance is additive, whereas transmission is not.

(73) Principle of the Method:

(74) The method was developed by Macnair & Smirnoff (Commun. Soil Sci. Plant Anal. 1999, 30, 1127-1136) for Arabidopsis halleri and Mimulus guttatus. It was subsequently used for Thlaspi caerulescens. The measurements can be averages (for the entire plant: above-ground part and/or underground part) or one-off measurements (for a piece of leaf or root). The plant samples are digested by sulphosalicylic acid, in which the zinc will dissolve slowly. A buffer solution at pH 9.6 makes it possible to adjust the pH of the samples to values that are compatible with the chelation of the zinc by the zincon. The zincon solution is then added in a set quantity. The sampling is carried out using standard solutions made up of sulphosalicylic acid and zinc sulphate. The quantity of zincon must remain greater than the quantity of zinc in the sample. In this way, the chelator is not saturated, all the zinc content in the sample is capable of being measured, and the absorbance value is situated within the standard range. A blue colouration of the sample after the addition of zincon indicates its saturation, hence the need for dilution before the measurements.

(75) Reagents:

(76) 2% Solution of Sulphosalicylic Acid

(77) (C.sub.7H.sub.6O.sub.6S, 2H.sub.2O; M=254.21 g.Math.mol.sup.−1; irritant to eyes and skin; in case of contact with the eyes, wash immediately with plenty of water and take medical advice)

(78) Weigh 20 g of powdered sulphosalicylic acid into a 250 mL beaker Add pure water and place under magnetic stifling until completely dissolved Pour into a 1 L (or 500 mL) volumetric flask and top up to 1 L with pure water Stir the final solution by hand
Buffer Solution pH=9.6 Calibrate the pH-meter (see protocol for use of the pH-meter) Weigh 7.5 g of potassium chloride (KCl; 74.55 g.Math.mol.sup.−1) into a 250 mL beaker Weigh 6.2 g of orthoboric acid (H.sub.3BO.sub.3; M=61.83 g.Math.mol.sup.−1) into a 250 mL beaker Add pure water to each beaker and place under magnetic stirring until completely dissolved Pour the contents of both beakers into a single 1 L beaker and top up to 800 mL with pure water Place under magnetic stirring and place the electrode of the pH-meter in the solution Prepare 100 mL of 2M a potassium hydroxide solution, i.e. 11.22 g in 100 mL of pure water (KOH; M=56.11 g.Math.mol.sup.−1; R22-35: harmful if swallowed, causes serious burns; S26-36/37/39-45: in case of contact with the eyes, wash immediately with plenty of water and take medical advice, wear suitable protective clothing). Using the KOH solution, gradually bring the pH to 9.6 (volume added approximately 50 mL) Pour 1 L (or 500 mL) into a volumetric flask and top up to 1 L with pure water Stir the final solution by hand
25 mM Zinc Sulphate
(ZnSO.sub.4, 7H.sub.2O; M=287.54 g/mol; R36/38-50/53: irritant to eyes and skin, very toxic to aquatic organisms, can lead to harmful long-term effects for aquatic organisms; S22-25-60-61: do not inhale dust, avoid contact with the eyes, dispose of the product and its container as a hazardous product, prevent release into the environment) Weigh 0.719 g of ZnSO.sub.4, 7H.sub.2O into a 100 mL beaker Add less than 100 mL of 2% sulphosalicylic acid and place under magnetic stirring until completely dissolved Pour the contents of the beaker into a 100 mL volumetric flask, and top up to 100 mL with sulphosalicylic acid (or weigh 7.19 g and place 10 mL in 100 mL)
0.03% Zincon Solution to be Prepared Just Before Use Weigh 0.03 g of zincon powder (kept under vacuum in a desiccator) per 100 mL of aqueous solution into a beaker. Add the required volume of pure water and place under magnetic stirring in a desiccator under vacuum until completely dissolved Stir gently by hand before each use (undissolved powder may remain)
Apparatus:

(79) The device used is the Helios γ spectrophotometer. Special 1 mL cells are arranged on a carousel. A light beam of a given wavelength passes through the cells on their polished face. The carousel comprises 7 positions. Position no. 1 receives the reference sample serving to provide the absorbance zero (0 nmol of zinc in the sample). The other 6 positions receive the samples containing the zinc to be assayed. In order to read the absorbance values, it is sufficient to rotate the carousel manually in order to successively arrange the cells opposite the light beam.

(80) Calibration:

(81) Standard Solutions (1 mL Volumes)

(82) Prepare 6 Eppendorf tubes by writing the number of moles in 20 μL (volume of a sample) of standard solution Distribute the different volumes of 25 mM stock solution into the tubes, using a 20-200 μL pipette, using a different tip for each tube Top up the volumes to 1 mL with 2% sulphosalicylic acid using a 100-1000 μL pipette
Constructing the Calibration Line 1. Turn on the spectrophotometer using the button at the rear of the device. 2. Wait until the device has carried out all the tests. 3. Adjust the wavelength by pressing the button corresponding to λm then enter the wavelength+ENTER. 4. Check that the device is in absorbance mode (in MODE select ABS). 5. Place 780 μL of buffer solution in each 1 mL cell, using the 100-1000 μL pipette. 6. Add 200 μL of zincon using the 20-200 μL pipette; the colour of the mixtures varies from orange to blue (blue=saturation of the chelator). 7. Add 20 μL of standard solution using the 20-200 μL pipette. 8. Homogenize the mixture in each cell using the 20-200 μL pipette and the tips that were used for sampling the standard solutions. 9. Place the cells on the carousel of the spectrophotometer (take care with the orientation with respect to the light beams), such that the “0 nmol” cell is in position no. 1, “10 nmol” in position no. 2, etc. 10. Press on “zero base”, the device zeros the absorbance for cell no. 1 11. Turn the carousel anticlockwise one position, the absorbance is then indicated for cell no. 2, etc. up to cell no. 7. 12. Check that the absorbance as a function of the concentration of the standard solution follows a linear relationship (Beer-Lambert law), and note the gradient of the line. 13. Optionally, take replicates; check the pH of 10 mL of mixture for spectrophotometry, for 0, 40 and 80 nmol. 14. The gradient of this line is used for calculating the zinc content of the samples. The gradient is the denominator.
Sampling:
Preparation of the Samples for Estimating the Average Zinc Concentration: Cut the plant portion for analysis (leaves or roots) into small fragments (fresh matter) or grind dry with a mortar (dry matter) for each individual plant Mix the fragments and distribute into several Eppendorf tubes (at least 4 per individual plant), at a rate of 50 to 100 mg of material per Eppendorf tube (approximately half filling); the mass of the samples is measured accurately by setting the scales to zero for each Eppendorf tube before weighing a sample If the plant matter is fresh, make a small hole in the stopper of the Eppendorf tubes before immersing them for 30 minutes in liquid nitrogen (allow to float in a polystyrene container closed with a lid) Add 1000 to 1500 μL of 2% sulphosalicylic acid: the lower volumes are used when the mass of tissues is low and when the expected zinc concentration is low Allow the digestion of the tissues by the acid to take place overnight Dilution: take 100 microlitres of the sample and pour it into another Eppendorf tube. Then add 300 microlitres of sulphosalicylic acid in order to obtain a ×4 dilution. 700 microlitres must be added for a ×8 dilution.
Preparation of the Samples for One-Off Measurements: Cut the plant portion for analysis (leaves or roots) into small fragments (fresh matter) or grind dry with a mortar (dry matter) for each individual plant Place the fragments in an Eppendorf tube at the rate of 5 to 50 mg of material per Eppendorf tube; the mass of the samples is measured accurately by setting the scales to zero for each Eppendorf tube before weighing a sample If the plant matter is fresh, make a small hole in the stopper of the Eppendorf tubes before immersing them for 30 minutes in liquid nitrogen (allow to float in a polystyrene container) Add 1000 to 1500 μL of 2% sulphosalicylic acid: the lower volumes are used when the mass of tissue is low and when the expected zinc concentration is low Allow the digestion of the tissues by the acid to take place overnight Dilution: take 100 microlitres of the sample and pour it into another Eppendorf tube. Then add 300 microlitres of sulphosalicylic acid in order to obtain a ×4 dilution. 700 microlitres must be added for a ×8 dilution.
Operating Method:

(83) 1. Switch on the spectrophotometer 2. In each 1 mL cell: 3. Place 780 μL of buffer using the 100-1000 μL pipette 4. Add 200 μL of freshly prepared zincon using the 20-200 μL pipette 5. Take a 20 μL sample using the 20-200 μL pipette; if necessary in order to sample a clearer liquid, centrifuge the Eppendorf tube at 10000 rpm for approximately 8 minutes 6. Homogenize the mixture in each cell using the 20-200 μL pipette and the tips that were used for taking the samples. 7. Note the colour of the sample; if necessary (blue solution=saturated chelator) dilute the sample while trying to take as much of it as possible during the dilution 8. Measure the absorbance at 606 nm by spectrophotometry, and deduce therefrom the zinc content of the sample (in nmol) by means of the calibration line
Important Note:
Zincon is sensitive to oxidation, therefore store the powder protected from air (in a vacuum bell jar), protect the solution ready for use, and do not keep it for more than one day.

Example 3

Reactions with the Zinc Catalyst of Example 1

(84) 3.1: Halogenation of the Alcohols with a Catalyst the Metal of which is Zn

(85) Example of the Secondary Alcohols (General Procedure):

(86) From 0.5 to 2 mmoles, in particular 1 mmole of alcohol (depending on the alcohol used) is added to the reaction mixture of Example 1.1 or 1.2 at 25° C.

(87) The average stifling time is 8 hours at 20° C. The chlorinated derivative can be isolated by the addition of petroleum ether, extraction, washing with a solution of sodium hydrogen carbonate, drying over calcium chloride and removal of the petroleum ether.

(88) A Beilstein test and GC MS analysis (VARIAN Chrompack CP 3800 Gas Chromatography/Varian MS Saturn 2000-Column optima 5; 30 m-0.25μ-flow rate: 1 mL/min-Programme: 50° C.: 2 minutes/100° C. (increase: 5° C./min); 12 minutes/150° C.); (increase: 20° C./min); 150° C.: 16 min; (increase: 50° C./min); 250° C.: 17 min) confirm the formation of the chlorinated derivative.

(89) Extension of the Method to the Tertiary and Secondary Benzyl Alcohols:

(90) These alcohols were tested under the same conditions. The reaction is rapid (30 minutes).

(91) Extension of the Method to the Primary Alcohols:

(92) The method is comparable, but the chlorination reaction is more difficult. Heating at a high temperature (reflux of the reaction medium) was carried out for 10 hours.

(93) Table XI below shows the same reactions carried out with a catalyst obtained with 12N HCl, used crude (Example 1.1) or purified (Example 1.2) as well as a comparison with the Lucas reaction carried out according to the standard conditions well known to a person skilled in the art:

(94) TABLE-US-00012 TABLE XI MW 102.10 102.10 136.09 102.10 156.27 Number of moles 0.5 to 2 mmol 0.7 to 1 mmol 0.7 to 1 mmol 0.7 to 1 mmol 1 mmol Conditions and Catalyst Crude catalyst Crude catalyst Catalyst purified on Catalyst catalyst used purified on 10 hours at 10 hours at Amberlyte resin purified on Amberlyte resin 25° C. 25° C. 10 hours at 25° C. Amberlyte 10 h to 25° C. resin 10 hours at 25° C. Products 2-chloro-4- 2-chloro-2- 1-chloro-1- 1-chloro-1-hexane: Chloro- obtained and methyl pentane: methyl pentane: phenyl 28% menthane: yield 54% 47% propane: 2-chloro-1-hexane: 94% 2-chloro-2- 3-chloro-3- 90% 15% Menth-3- methyl pentane: methyl pentane: ene: 5% 44% 53% Menth-2- 3-chloro-3- ene: 1.5% methyl pentane: Bicyclo <1% Menthol: 0% 2-methyl- pentan-2-ol: 2% Comparison with 8 hours at 25° C. 8 hours at 25° C. 2 hours at Chloromenthane: the Lucas 2-chloro-4- 2-chloro-2- 25° C. 94% standard reaction methyl pentane: methyl pentane: 1-chloro-1- Menth-3- 54% 47% phenyl ene: 5% 2-chloro-2- 3-chloro-3- propane: Menth-2- methyl pentane: methyl pentane: 100% ene: 1.5% 44% 53% Menthol: 0% 3-chloro-3- methyl pentane: <1% 2-methyl- pentan-2-ol: 2%

(95) 3.1: Electrophilic Aromatic Substitution

(96) The catalyst used is crude (Example 1.1 with 12N HCl)

(97) It must be dispersed on montmorillonite or silica impregnated with metal oxide

(98) It can be recycled at least four times.

(99) 3.1.1: Friedel-Crafts Alkylation

(100) 217 mg of dry crude catalyst (Example 1.1 with 12N HCl) is dispersed and ground in a mortar with 174 mg of Montmorillonite K10, then heated to 110° C. in a crucible.

(101) The halogenated derivative (87 mmol) is added to 20 equivalents of the aromatic reagent.

(102) The previous solid is added in one go. The mixture is stirred for the time given in the table. The medium is filtered, then concentrated under vacuum. The medium is analysed by GC-MS and .sup.1H NMR.

(103) The results are shown in Table XII below:

(104) TABLE-US-00013 TABLE XII Yields of Compound A Compound B conditions regiomers comments 0  1 hour 2.5% Many by- products 2 of which are adducts of Zn  1 hour  11%  1 hour 100% Ortho: 18% Para: 82%  1 hour 100% Ortho: 18% Para: 82% Recycled catalyst  1 hour  9 h 14 h 30% 52% 69% 0  1 hour 14 h  0% 89% Ortho: 31% Para: 69%  1 hour 14 h 52% 98% 14 h 31% Ortho: 30% Para: 70% 10 min 100% Ortho: 40% Para: 60%

(105) 3.1.2: Friedel-Crafts Acylation

(106) Colouring Agents:

(107) Phenolphthalein

(108) 500 mg of phthalic anhydride, 500 mg of phenol and 1 g of crude catalyst derived from Thlaspi (Example 1.1, 12N HCl) dehydrated at 110° C. for a few minutes are placed in a single-necked flask and heated at 80° C. for 5 minutes.

(109) After cooling down, the reaction mixture is diluted in 5 mL of a water/ethanol mixture. 1 mL of solution is taken then added to a 3M soda solution.

(110) In the case of phenolphthalein, the solution becomes pink immediately.

(111) After washing with ether, the phenolphthalein crystallizes easily.

(112) Fluorescein

(113) 500 mg of phthalic anhydride, 500 mg of resorcinol and 2 g of crude catalyst derived from Thlaspi (Example 1.1, 12N HCl) dehydrated at 110° C. for a few minutes are placed in a single-necked flask and heated at 80° C. for 5 minutes.

(114) After cooling down, the reaction mixture is diluted in 5 mL of a water/ethanol mixture. 1 mL of solution is taken then added to a 3M soda solution.

(115) For fluorescein, the basic mixture is poured into a dilute ammonia solution. A bright fluorescent yellow solution shows that fluorescein has been formed.

(116) Ortho or Para Ethyl Acetophenone

(117) Place 5 mL of anhydrous toluene in a three-necked flask, then introduce 4.5 g of catalyst (Example 1.1, 12N HCl) in one go. Add 0.7 mL of acetic anhydride dropwise. Heat for 30 minutes at 100° C. Leave to cool down and pour the reaction mixture onto an ice-cold solution of concentrated hydrochloric acid (10 mL). Pour into a separating funnel, then separate the organic phase. Wash the latter with water, then with an aqueous solution of ammonium chloride at pH=7.

(118) Dry the organic phase over anhydrous sodium sulphate.

(119) The results are shown in Table XIII:

(120) TABLE-US-00014 TABLE XIII Yields of Compound A Compound B conditions regiomers comments 30 min 95% Ortho: 40% Para: 60% 0  5 min 90% Extraction with ether Mp° C.: 258- 263 Colour test at pH 9  5 min 90% Washing with EtOH 20° C.- showing fluorescence under UV

(121) 3.2: Synthesis of 3,4-dihydropyrimidin-2(1H)-one or 3,4-dihydropyrimidin-2(1H)-thione (Biginelli Reaction)

(122) ##STR00033##

(123) Protocol:

(124) 3 g of zinc dichloride originating from the catalyst derived from Thlaspi (Ganges Ecotype), purified on Amberlyte resin (Example 1.2.1) and dehydrated (110° C., 2 hours)) is dispersed in 10 g of K100 silica. The mixture is finely ground and placed in 60 mL of anhydrous toluene. The reaction mixture is brought to reflux for 10 hours, filtered and the solid residue is heated at 110° C. for 12 hours. A solution of 2.5 mmol of benzaldehyde, 2.5 mmol of urea (or of thiourea) diluted in 15 mL of anhydrous acetonitrile is then added. The mixture is brought to reflux for 10 hours. The reaction is easily monitored by TLC (UV development-eluent: pure diethyl ether) and the mixture is filtered. It is purified by crystallization from the EtOAc-hexane mixture. The yield is 80%. The pure product is characterized by its melting point, .sup.1H NMR, .sup.13C NMR, COSY and HSQC and IR.

(125) 3.3: Cycloaddition Reactions

(126) Diels-Alder: Cyclopentadiene and Diethyl Fumarate)

(127) ##STR00034##

(128) Protocol:

(129) A 1M solution of catalyst derived from Thlaspi (Ganges Ecotype), purified on Amberlyte resin (Example 1.2.1) and dehydrated (150° C., 2 hours) is prepared in anhydrous toluene. This solution is added to a solution of diethyl fumarate (2.5 mmol) in 15 mL of toluene. After stifling for 30 minutes, freshly distilled cyclopentadiene (3 mmol) is added. The reaction mixture is stirred for 15 minutes, then the solution is hydrolyzed by a saturated aqueous solution of sodium hydrogen carbonate.

(130) The aqueous phase is extracted with ether (3×20 mL). The organic phases are combined, dried over sodium sulphate and concentrated under vacuum.

(131) The adduct is characterized by GC-MS, .sup.1H and .sup.13C NMR. The reaction is quantitative and perfectly diastereoselective: no isomerization is observed.

(132) The stereoselectivity of the reaction was studied on menthyl fumarate:

(133) ##STR00035##

(134) The reaction is quantitative after stirring for 1 hour at −20° C.

(135) The diastereomeric ratio is 2.3.

(136) This result has not been optimized and can be optimized by adjusting the quantity of catalyst and by studying the effect of the solvent.

(137) 3.4: Transesterification Reactions

(138) ##STR00036##

(139) A reaction model was studied with methyl palmitate (270 mg, 1 mmol) and butan-1-ol (5 mL). 100 mg of dehydrated catalyst originating from Thlaspi was added; the mixture was heated for 5 hours, then 10 hours and analyzed by GC-MS.

(140) If the catalyst is used in the crude state (Example 1.1, 12N HCl), the reaction exhibits a degree of conversion of 13%.

(141) If it is purified with amberlyte resin (Example 1.2.1), it is 60%.

Example 4

Modelling a Halogenation Reaction Carried Out in a Metallophyte Species

(142) 1) Preparation of zinc malate, in order to cultivate the species in which zinc is present, T. caerulecens, in the laboratory;

(143) 2) Preparation of zinc chloride from zinc malate;

(144) 3) Halogenation of a secondary alcohol using the zinc chloride prepared previously.

(145) Implementation of these transformations is carried out as follows:

(146) 1) the zinc malate is prepared by the action of activated powdered zinc (prior activation by Me.sub.3SiCl) on malic acid (Aldrich 088K0026). As the latter is solid, a partial dissolution and homogenization of the medium are carried out using 4-methyl-pentan-2-ol. This alcohol acts both as a solvent throughout the method and as a specimen alcohol in the halogenation reaction; the release of hydrogen, then the total dissolution of the zinc make it possible to follow the progress of the reaction.

(147) The reaction requires heating to 50° C. in order to ensure total zinc consumption, a condition necessary so that the reaction sequence is significant (otherwise the zinc reacts with HCl in the following step to form ZnCl.sub.2 directly).

(148) ##STR00037##

(149) 2) the addition of an excess of hydrochloric acid to the zinc malate allows the zinc dichloride to be formed by simple acid-base reaction and results in the in situ preparation of the Lucas reagent.

(150) ##STR00038##

(151) 3) As the ZnCl.sub.2/HCl mixture is formed in the presence of 4-methyl-pentan-2-ol, the halogenation reaction starts as soon as HCl is added.

(152) ##STR00039##

(153) After stirring for 15 minutes at ambient temperature, the reaction mixture is treated. The conversion rate evaluated by GC MS is 60%.

(154) Conclusion

(155) The reaction sequence carried out in a plant medium is therefore perfectly modelled under standard synthesis conditions.

(156) Experimental Part

(157) 2.534 g of malic acid (0.0189 mol) in solid form, as well as 2.472 g of zinc metal (0.018 mol) in powder form are successively introduced into a 100 mL single-necked flask provided with water-cooled condenser, and 4-methyl-pentan-2-ol (7 mL) is added in order to disperse the solids and facilitate the stifling of the reaction medium in which the malic acid is partially soluble.

(158) The mixture is taken to reflux for 4 hours at 50° C., then it is returned to ambient temperature under stifling for 12 hours until all of the zinc metal has been consumed.

(159) 12N hydrochloric acid (6 eq.) is then added to the mixture in order to produce ZnCl.sub.2.

(160) Finally, the excess of 4-methyl-pentan-2-ol reacts with the regenerated malic acid in order to produce 2-chloro-4-methyl-pentane. 15 mL of ether is added to extract the chlorinated derivative. After decantation and separation of the aqueous and organic phases, the ether phase is washed twice with 10 mL of water then dried over magnesium sulphate. The solution is filtered then concentrated. The crude mixture is distilled (bp=131-134° C.). 60% of 2-chloro-4-methylpentane (1.285 g) is isolated pure.

(161) The solution is subjected to the Beilstein test in order to indirectly check the presence of ZnCl.sub.2. The test is positive. The formation of the chlorinated derivative is easily confirmed by mass spectrometry (m/z: 135 and 137).

Example 5

Preparation of a Composition Containing a Metal Catalyst the Metal of which is Ni

Example 5.1

Sebertia acuminata plant

(162) 10 g of stems and twigs of Sebertia acuminata are calcined. 4.5 to 5 g of nickel is thus obtained. The ash is placed in a beaker containing 30 mL of 12N HCl. The mixture is stirred vigorously for 30 minutes at 50° C.

(163) The mixture is filtered, then the filtrate is concentrated and dehydrated at 110° C. in order to obtain a dehydrated composition containing an NiCl.sub.2 catalyst.

Example 5.2

Psychotria douarrei Plant

(164) Calcining:

(165) The calcining is carried out according to the standard programme (300° C. for 2 hours, then 550° C. for 3 hours).

(166) Preparation of the Catalyst:

(167) 1 g of Psychotria douarrei ash is taken. A minimum of 12N HCl is added to the ash (approximately 20 mL); all of the solid passes into solution and rapidly becomes a pale green colour. After 2 hours at 60° C., the mixture is evaporated at 80° C., filtered and produces 1 g of a fine powder having a pale yellow colour, the colour of dehydrated nickel dichloride.

(168) Results of ICP-MS (Table XIV):

(169) TABLE-US-00015 TABLE XIV Mg Al Ca Fe Cu Zn Cd Pb Mn Ni Ash 87020 880 105945 260 4740 7040 20 300 260 185600 Crude catalyst 78240 1620 93719 1760 4560 5760 14 360 1160 270320

(170) Selective Precipitation:

(171) Principle:

(172) See FIG. 4

(173) Precipitation is carried out at pH=7 by adding 1M soda to 100 mg of catalytic solid diluted in 2 mL of 1M HCl. The precipitate appears from pH ˜6.5

(174) The heterogeneous solution is centrifuged, dried (100 mg recovered) and analyzed by ICP-MS (5 mg/50 mL of 2.5% HNO.sub.3). The solid is pale green.

(175) Results of ICP-MS (Table XV):

(176) TABLE-US-00016 TABLE XV Catalyst Mg Al Ca Fe Cu Zn Cd Pb Mn Ni Precip- 9237 1500 62019 640 4660 5800 30 300 540 331028 itated at pH = 7

(177) The crude catalyst (Example 5.2) has been the subject of developments in organic synthesis.

(178) It is very efficient: the test electrophilic aromatic substitution reaction between toluene and benzyl chloride (Cf. operating method described with K10 montmorillonite, Example 3.1.1) is 80% after reaction for 1 hour at 20° C. the Diels-Alder reaction between diethyl fumarate and cyclopentadiene is very rapid: it is completed after stirring for 15 minutes at 20° C.; this result opens up new prospects for asymmetric synthesis. The efficiency of the catalysis by nickel dichloride and the ease of the reaction make it possible to carry out tests at a low temperature in order to promote high asymmetric induction with dimenthyl fumarate. The Biginelli reaction is also possible and comparable to the previous tests. It is comparable to the test with pure hydrated NiCl.sub.2 described in the literature (Jun Lu, Yinjuan bai, Synthesis 2002, 4, 466).

(179) These results are original, as with the exception of the Biginelli reaction, NiCl.sub.2 is rarely used in Lewis acid catalysis.

(180) An advantage of the method is that the treatment of the plant makes it possible to produce different nickel salts from a single precursor: P. douarrei. The benefit is to have available catalytic systems of different solubility and varying applications. The successful tests are as follows:

(181) See FIG. 5

Example 6

Preparation of Dichlorbis(Triphenylphosphine)Nickel(II), an Arynic Coupling Catalyst

(182) The composition of Example 5.1 (NiCl.sub.2, 6H.sub.2O) is taken up in 50 mL of dry ethanol and heated to 80° C.

(183) Triphenylphosphine (11 g) is dissolved in 100 mL of dry isopropanol under a nitrogen atmosphere. The mixture is stirred under reflux until the triphenylphosphine is completely dissolved. It is then added to the hot nickel dichloride solution (NiCl.sub.2) prepared above. The solution is stirred under reflux for 30 minutes then brought to ambient temperature.

(184) The mixture is filtered then the residual solid is washed with cold ethanol (40 mL), then ether (20 mL). The solid, dichlorobis(triphenylphosphine)nickel(II), is dried under a flow of nitrogen.

Example 7

Preparation of Nickel (0) from the NiCl2 Catalyst of Example 5.1 Isolated from Sebertia acuminata

(185) 2 g of dehydrated NiCl.sub.2 (Example 5.1) is placed in 50 mL of 95% ethanol, then heated to 80° C. until maximum dissolution of the salts. 1 mL of a 6N hydrochloric acid solution is added. 2.5 g of aluminium in grains (100 microns) is added in small portions (0.5 grams at a time) at a rate which makes it possible to maintain the release of dihydrogen. If the green nickel salts are not completely consumed after all the aluminium has been added, a few additional grains are added. The mixture is filtered immediately on a frit. The solid (Ni(0)) is poured rapidly into a soda solution (50 mL of 20% NaOH). Stirring is maintained for 30 minutes at 60° C. The excess soda is removed and the catalytic solid is washed 5 times with 50 mL of distilled water.

Example 8

Reduction of 1-phenyl 2-nitroprene in 1-phenyl 2-aminopropane

(186) This method illustrates an application of the method in the double reduction of a C═C double bond and the nitro group.

(187) 2.5 g of 1-phenyl 2-nitropropene are placed in 25 mL of ethanol then added to an ethanolic nickel solution (2 g NiCl.sub.2 (Example 5.2) in 50 ml of EtOH).

(188) 1.5 mL of hydrochloric acid are added slowly, then 10.5 grams of aluminium are introduced slowly. After dissolution of the aluminium, 4 mL of HCl then 0.8 g of aluminium are added alternately.

(189) Repeat this successive addition of HCl and aluminium twice.

(190) The consumption of the aluminium is slow and needs 5 to 6 hours of reaction. The medium is then neutralized carefully using an aqueous soda solution. The reaction is highly exothermic.

(191) After 30 minutes, the organic phase becomes orange, which indicates the formation of the expected amine. After decantation and concentration, the crude syrup obtained is taken up in acetone.

(192) The addition of sulphuric acid precipitates the ammonium sulphate derived from the 1-phenyl 2-aminopropane, which is isolated by filtration. The overall yield of 1-phenyl 2-aminopropane is 65%.

Example 9

Preparation of a Composition Containing a Metal Catalyst, the Metal of which is Cu

(193) 9.1: Catalyst Originating from Ipomea alpina

(194) The catalyst is prepared in the same way as for the Zn or the Ni, from Ipomea alpina (12N HCl).

(195) 9.2: Catalyst Originating from Bacopa monnieri

(196) Cultures and accumulation of Cu(II) (CuSO.sub.4) according to S. Sinha and P. Chadra, Water, Air and Soil Pollution 51:271-276, 1990.

(197) Calcining:

(198) 4 plants having accumulated copper sulphate for 8 days are washed copiously (significant calcareous deposit), dried with filter paper then placed in an oven for 2 hours at 65°. The calcining is then carried out according to the standard programme (300° C. for 2 hours, then 550° C. for 3 hours).

(199) Preparation of the Catalyst:

(200) 140 mg of ash is taken. A minimum amount of 1N HCl is added to the ash (approximately 2 mL); after an effervescence of short duration, almost all of the solid passes into solution; the solution rapidly becomes clear and becomes grey-yellow, which makes it possible to assume the formation of copper chloride. The solution is even yellow-green after stirring for 2 hours. After rapid filtration, the mixture is evaporated at 80° C. and leads to 475 mg of a fine rust-coloured powder (Table XVI):

(201) TABLE-US-00017 TABLE XVI Run Mg Al Ca Fe Cu Zn Cd Pb ppm ppm ppm Fe ppm ppm ppm ppm Cat. Bacopa 8114 5496 125880 5676 30060 2328 412 1578

(202) 9.3: Catalyzed Hydrolysis of Thiophosphates

(203) The catalyzed hydrolysis of thiophosphate is illustrated in FIG. 2, in which parathion is detoxified by a catalyst prepared from Bacopa monnieri or Thlaspi caerulescens.

(204) 2 mL of a 1:1 water/ethanol solution at pH=8.0 is introduced into a 5 mL flask.

(205) 140 mg of catalyst (Example 9.2) is added to the present solution.

(206) The mixture is stirred at 40° C.

(207) 5.5 μL of parathion (stored at 5° C.) is added using a GC micro-syringe through a septum. Stirring is maintained for 30 minutes at 40° C.

(208) The equipment contaminated with parathion (micro-syringe) is washed with 3 M soda, in order to remove the parathion.

(209) The decomposition of the parathion is monitored by .sup.31P NMR: it proceeds more quickly and further than without Bacopa [(EtO).sub.2P(O)O.sup.−: +20% in 30 hours including 12% diethyl phosphate].

(210) The reaction can also be carried out by a crude catalyst originating from Thlaspi caerulescens (Puy de Wolf Ecotype) obtained as in Example 1.1 but with a lower yield.

Example 10

Development of Oximes

Example 10.1

(211) A 0.5% CuCl.sub.2 solution (Example 9.1) in water is prepared and vaporized on an oxime previously deposited on a silica-covered thin-layer chromatography plate.

(212) A green-brown mark appears easily. It is characteristic of the oxime-Cu.sup.2+ complex.

Example 10.2

(213) A 0.5% CuCl.sub.2 solution (Example 9.2) in water is prepared and 2 mL of the solution obtained is placed in a test tube (pale grey-green solution). A few mg of benzaldehyde-oxime (E) are added to the solution. After stirring for a few seconds, a dark green complex appears clearly, characteristic of the oxime-Cu.sup.2+ complex.

Example 11

Electrophilic Aromatic Substitution Reaction by a Metal Catalyst Isolated from Plants Accumulating Metals Such as Zn, Cu or Ni

(214) The catalyst obtained in Example 1 (ZnCl.sub.2), Example 5 (NiCl.sub.2) or Example 9 (CuCl.sub.2) is dehydrated by heating at 110° C., then impregnated with montmorillonite (2 g of montmorillonite per 1.46 g of ZnCl.sub.2 for example). The mixture is at 110° C. for 1 hour.

(215) The ZnCl.sub.2-montmorillonite catalytic complex is added to the toluene mixture (20 mL) and benzyl chloride (1.27 g).

(216) After stirring for 1 hour, the mixture is filtered and the filtrate washed with hexane. The isomeric electrophilic substitution products, 4- and 2-methyldiphenylmethane are obtained quantitatively.

Example 12

Comparative Example of a Halogenation Reaction of a Secondary Alcohol Carried Out with a Composition Containing a Catalyst, Obtained without Filtration (Step d.)

(217) 30.03 g of dehydrated and powdered leaves of Thlaspi caerulescens originating from the soil of the mine of Avinières are assayed by the zincon method. The level of zinc present in the dry matter obtained is 420 mg or 2 mmoles. The dry matter is then placed in 20 mL of 1N hydrochloric acid.

(218) The solution is stirred for 1 hour, then sonicated for 2 hours. 1 to 2 mL of 12N HCl is added in order to allow satisfactory stirring of the medium.

(219) 2 mmoles of 4-methyl pentan-2-ol are added directly, without filtration, to the previous reaction mixture at 25° C. A very heterogeneous dark green solution is stirred for 5 hours at 40° C., a sample of the reaction medium is place in a few mL of petroleum ether and analyzed by GC MS. Only traces of chlorinated derivative are observed.