Mixed alkyl terminated polyether dendrons

Abstract

A polyether dendrimer of formula (I), ##STR00001##
wherein the symbols and indices have the following meanings: each Y is independently [R.sup.1(OCH.sub.2CH.sub.2).sub.pO]; each Z is independently [R.sup.2(OCH.sub.2CH.sub.2).sub.q(OCH(CH.sub.3)CH.sub.2).sub.rO]; each R.sup.1 is independently H, CH.sub.3 or C.sub.2-C.sub.4-alkyl; each R.sup.2 is independently linear or branched C.sub.8-C.sub.22-alkyl; X is H or C.sub.1-C.sub.4-alkyl; m is 1, 2, 3, 4, 5 or 6; n, o are rational positive numbers >0, with the proviso that the sum of n and o is 2.sup.m; p is a natural number from 5 to 50; q is a natural number from 1 to 50; r is 0 or is a natural number from 1 to 30, with the proviso that 5q+r50, and denotes the bonding of the respective group to the dendron scaffold,
is useful for solubilizing sparingly-water soluble active ingredients, in particular pesticides.

Claims

1. A composition, comprising a) a polyether dendron of formula (I), ##STR00006## wherein the symbols and indices have the following meanings: each Y is independently [R.sup.1(OCH.sub.2CH.sub.2).sub.pO]; each Z is independently [R.sup.2(OCH.sub.2CH.sub.2).sub.q(OCH(CH.sub.3)CH.sub.2).sub.rO]; each R.sup.1 is independently H, CH.sub.3 or C.sub.2-C.sub.4-alkyl; each R.sup.2 is independently linear or branched C.sub.8-C.sub.22-alkyl; X is H or C.sub.1-C.sub.4-alkyl; m is 1, 2, 3, 4, 5 or 6; n, o are rational positive numbers >0, with the proviso that the sum of n and o is 2.sup.m; p is a natural number from 5 to 50; q is a natural number from 1 to 50; r is 0 or is a natural number from 1 to 30, with the proviso that 5q+r50, and denotes the bonding of the respective group to the dendron scaffold; and b) a pesticidal active ingredient.

2. The composition of claim 1, wherein the pesticidal active ingredient has a maximum solubility in water of 10 g/l at 20 C.

3. A process for producing the composition according to claim 1, comprising the step of contacting a polyether dendron of formula (I) and a pesticidal active ingredient.

4. A method for controlling phytopathogenic fungi or undesired vegetation or insect or acarid infestations or for regulating the growth of plants, comprising the step of applying a pesticidal composition according to claim 2 to the pests or undesired plants, to plants to be protected and/or to the soil where the plants to be protected or the undesired plants grow.

5. The method of claim 4, wherein the polyether dendron has a molecular weight of 1000 to 15.000.

6. The method of claim 4, wherein group Y has a molecular weight of 300 to 2000.

7. The method of claim 4, wherein the weight ratio Y:Z is 13:1 to 1:3.

8. The method of claim 4, wherein the molar ratio of Y to Z is in the range of from 95:5 to 3:1.

9. The method of claim 4, wherein 70 to 100% of the groups Y and Z carry an end group R.sup.1 or R.sup.2.

10. The composition of claim 1, wherein the symbols and indices in formula (I) have the following meanings: X is H; each Y is the same; each Z is independently [R.sup.2(OCH.sub.2CH.sub.2).sub.q(OCH(CH.sub.3)CH.sub.2).sub.rO] R.sup.1 is CH.sub.3; R.sup.2 is linear or branched, C.sub.8-C.sub.22-alkyl; m is 1, 2 or 3; n, o are positive rational numbers with the proviso that the sum of n and o is 2.sup.m; p is a natural number from 15 to 25; q is a natural number from 5 to 25, and r is 0 or is a natural number from 1 to 15.

11. The composition according to claim 1, wherein the polyether dendrons of formula (I) have a molecular weight of 1000 to 15.000.

12. The composition according to claim 1, wherein group Y in formula (I) has a molecular weight of 300 to 2000.

13. The composition according to claim 1, wherein the weight ratio Y:Z in formula (I) is 13:1 to 1:3.

14. The composition according to claim 1, wherein the molar ratio of Y to Z in formula (I) is in the range of from 95:5 to 3:1.

15. The composition according to claim 1, wherein 70 to 100% of the groups Y and Z in formula (I) carry an end group R.sup.1 or R.sup.2.

16. A process for preparing a polyether dendron of formula (I) ##STR00007## wherein the symbols and indices have the following meanings: each Y is independently [R.sup.1(OCH.sub.2CH.sub.2).sub.pO]; each Z is independently [R.sup.2(OCH.sub.2CH.sub.2).sub.q(OCH(CH.sub.3)CH.sub.2).sub.rO]; each R.sup.1 is independently H, CH.sub.3 or C.sub.2-C.sub.4-alkyl; each R.sup.2 is independently linear or branched C.sub.8-C.sub.22-alkyl; X is H or C.sub.1-C.sub.4-alkyl; m is 1, 2, 3, 4, 5 or 6; n, o are rational positive numbers >0, with the proviso that the sum of n and o is 2.sup.m; p is a natural number from 5 to 50; q is a natural number from 1 to 50; r is 0 or is a natural number from 1 to 30, with the proviso that 5q+r50, and denotes the bonding of the respective group to the dendron scaffold; comprising the steps of reacting n moles (CYH) and o moles (ZH) with (n+o)/2 moles of glycerol or a reactive derivative thereof at a temperature of 20 to 200 C. and optionally in the presence of a catalyst and optionally repeating the step of reacting with glycerol or a reactive derivative thereof up to the number of m reactions, reacting each time half of the molar amount of glycerol or reactive glycerol derivative reacted in the last step.

Description

EXAMPLES

(1) Methyl polyethylene glycol (MPEG1) has a mean molar mass of 350 g/mol, an OH number of 160 mg KOH/g, and is commercially available. Methyl polyethylene glycol (MPEG2) has a mean molar mass of 1000 g/mol, an OH number of 60 mg KOH/g and is commercially available. C.sub.16-C.sub.18-Fatty alcohol polyethylene glycol (FAPEG) has a OH number of 80 mg KOH/g and is commercially available. The Ohio numbers were measured to DIN 53 240. The acid numbers were measured to DIN EN ISO 2114. GPC was carried out with polymethyl methacrylate (PMMA) as the standard.

Comparative Example 1

Synthesis of Polar Dendron C1

(2) A solution of 487 g of methyl polyethylene glycol MPEG1 in 600 ml of toluene was initially charged. 55.8 g of sodium hydroxide were added while stirring. The mixture was heated to 100 C., and 64.4 g of epichlorohydrin in 129 ml of toluene were added dropwise within 30 min. The mixture was then stirred at 100 C. for 2 h. Subsequently, 32.2 g of epichlorohydrin in 64 ml of toluene were metered in at 100 C. within 20 min. The mixture was then stirred at 103 C. for 2 h. Finally, 16.1 g of epichlorohydrin in 32 ml of toluene were metered in at 100 C. within 15 min, and the mixture was then stirred at 103 C. for another 20 h.

(3) The resulting brown, turbid mixture was cooled to room temperature and filtered. Toluene was distilled off. The clear brown product C1 was characterized by GPC (Mn=2000 g/mol, Mw=2480 g/mol, in dimethylacetamide).

Example 1

Synthesis of Amphiphilic Dendron D1

(4) A solution of 136.7 g MPEG2 and 95.7 g FAPEG in 259 ml toluene was initially charged. 22.8 g of sodium hydroxide were added while stirring. The mixture was heated to 100 C. and then 12.8 g of epichlorohydrin in 26 ml of toluene were added dropwise within 30 min. The mixture was then stirred at 100 C. for 2 h. Subsequently, 6.4 g of epichlorohydrin in 13 ml of toluene were metered in at 100 C. within 20 min. Subsequently 3.2 g of epichlorohydrine in 6 ml of toluene were metered in at 100 C. within 15 min, and the mixture was stirred at 103 C. for a further 20 h. The resulting brown, turbid mixture was cooled to room temperature and filtered. Thereafter the toluene was distilled off. The clear brown product D1 was characterized by GPC (Mn=3670 g/mol, Mw=5910 g/mol in dimethylacetamide).

Example 2

Synthesis of Amphilic Dendron D2

(5) A solution of 240 g (1.818 mol) of 180.7 g MPEG2 and 56.5 g FAPEG in 258 ml toluene was initially charged. 20.94 of sodium hydroxide were added while stirring. The mixture was heated to 100 C. and then 12.1 of epichlorohydrin in 24 ml of toluene were added dropwise within 30 min. The mixture was then stirred at 100 C. for 2 h. Subsequently, 6.1 g of epichlorohydrin in 12 ml of toluene were metered in at 100 C. within 20 min. Then 3.0 g of epichlorohydrin in 6 ml toluene was metered in at 100 C. within 15 min, and the mixture was stirred at 103 C. for a further 20 h. The resulting dark brown, turbid mixture was cooled to room temperature and filtered. Thereafter the toluene was distilled off. The clear brown product D2 was characterized by GPC (Mn=3590 g/mol, Mw=5860 g/mol in dimethylacetamide).

Application Example 1

(6) Increased uptake and retention of pesticide in leaves:

(7) An aqueous suspension concentrate (SC3) was prepared containing 300 g/I fluxapyroxad, 1,2-propylene glycol, anionic phenolsulfonic acid-urea-formaldehyde condensate surfactant, sodium salt of naphthalene sulfonate condensate, antibacterial agent and antifoaming agent, thickener. The spray mixture was applied at a rate of 200 I/ha, 12.5 g/ha pesticide and 250 g/ha polyether dendron.

(8) The uptake of the pesticide in the leave was determined as described by Berghaus R, Nolte M, Reinold A 2010. Optimization of agrochemical formulations by adjuvants using lab track sprayer and HPLC-MS-MS analysis. In: Baur P and Bonnet M ed. Proc. 9th Intern. Symp. on Adjuvants for Agrochemicals. ISAA 2010 Freising, Germany. Pp. 239-244: Wheat plants (Triticumaestivum variety Melon) were used. Subsequently to spraying, the plants were cultivated again in the greenhouse under ambient conditions. After 8 days samples of 10-15 treated leaves were cut off and weighed. Leaves were cut into small pieces, and washed with 50% methanol in demineralized water as washing medium for 5 min. Then, the washing medium was separated from the leaves. The leaves were washed again with washing medium for 5 min. Both washing media were combined and diluted for analysis.

(9) Finally, the leaves were transferred to a vial containing the extraction medium (75% methanol, 20% water and 5% HCl) and homogenized using a Polytron PT 6100 dispersing unit (Kinematica, CH) for 2 min. 10 ml of the extract were centrifuged with 4000 rpm for 5 min. 2 ml of the supernatant were treated with 2 ml NaOH (0.2 mol/L) and 5 ml cyclohexane, and stirred for 30 min and centrifuged subsequently. 1 ml of the cyclohexane phase was transferred to a glass vial and dried (Liebisch N2 Evaporator, Germany). The residue was solubilized in methanol/water 50:50 and analyzed by HPLC-MS/MS. In addition, unsprayed plants were treated in the same way to see whether they are contaminated. Unsprayed leaves were spiked with standard active ingredient to determine the recovery of active ingredient during washing and extracting steps. According to the recovery rate the measured sample values were corrected. Retention (total amount of active found in and on the plant) is equal to the sum of active concentrations found during washing and extracting steps.

(10) The results that are given in Table 1 show that the usage of invented adjuvants drastically increases the uptake of pesticide. The comparative Graft Polymers GM 903/0211 and 227 and C2 are based on a hydrogen-terminated alkoxylate instead of an alcohol alkoxylate. The data showed that this modification resulted in an increased uptake and retention of the active.

(11) TABLE-US-00001 TABLE 1 Uptake (mg/kg leave) fluxapyroxad.sup.a) 0.4 fluxapyroxad + C1.sup.a) 0.4 fluxapyroxad + D1 0.8 fluxapyroxad + D2 0.9 .sup.a)Comparative not according to invention
Biology (Green House)

Application Example 2

Increased EfficacyComparative Data

(12) An aqueous suspension concentrate (SC1) was prepared containing 300 g/I fluxapyroxad (a fungicide, water solubility 4 mg/L at 20 C.) and common auxiliaries (such as 1,2-propylene glycol, anionic phenolsulfonic acid-urea-formaldehyde condensate surfactant, antibacterial agent, antifoaming agent, thickener).

(13) The pesticidal activity was tested in greenhouse tests on wheat variety Monopol, which were infected with the fungi Puccinia Recondata/Tritici. The plants were treated with SC1 three days after the inoculation at a use rate of 25, 8.25 or 2.75 g pesticide per ha (200 I water/ha). The use rate of the adjuvants was kept constant at 250 g per ha. The percentage of the infected leaf surface areas (7 days after inoculation) was summarized in Table 2.

(14) The data showed that compositions with the dendrons D1 and D2 according to the invention have a higher pesticidal activity compared to the control without the dendron.

(15) TABLE-US-00002 TABLE 2 % Use rate of active 100% 33% % infected leaf area C2.sup.a) Untreated 80% C3.sup.a) fluxapyroxad 79% 80% Ap. Ex. 2.1 fluxapyroxad D1 7% 31% Ap. Ex. 2.2 fluxapyroxad D2 12% 45% .sup.a)Comparative not according to invention

(16) The above greenhouse tests were also made with a suspension concentrate SC2 of the triazole fungicide 2-[4-(4-chlorophenoxy)-2-(trifluoromethyl)phenyl]-1-(1H-1,2,4-triazol-1-yl)propan-2-ol fungicide 2 (100 g/ha) instead of fluxapyroxad. The results are summarized in Table 3:

(17) TABLE-US-00003 TABLE 3 % Use rate of active 100% 33% % infected leaf area C4.sup.a) Untreated 89% C5.sup.a) fungicide 2 83% 91% Ap. Ex. 3 fungicide 2 6% 12% D1 .sup.a)Comparative not according to invention

Application Example 3

Solubilization of Pesticides

(18) Solubilization measurements were carried out with a highthroughput screening robot. This set up dosed 10 mg solid active and 500 m of the respective 3 wt-% liquid polymer solution (in CIPAC water D) into wells on a micro titer plate. After the addition of stirring bars and 24 hours incubation time the samples were filtrated via polypropylene filters in order to separate dissolved active and its solid form ated. The amount of solubilized active was determined via UV/VIS spectroscopy. The solubilities of various actives were summarized in Tables 4.

(19) TABLE-US-00004 TABLE 4 Increased solubility of fluxapyroxad Solubility in pmm fluxapyroxad alone.sup.a) 10 C1.sup.a) 19 D1 650 D2 409 .sup.a)Comparative not according to invention

(20) TABLE-US-00005 TABLE 5 Increased solubility of fipronil Solubility in pmm Fipronil.sup.a) 12 C1.sup.a) 14 D1 840 .sup.a)Comparative not according to invention

(21) TABLE-US-00006 TABLE 6 Increased solubility of the triazole fungicide 2-[4-(4-chlorophenoxy)-2- (trifluoromethyl)phenyl]-1-(1H-1,2,4-triazol-1-yl)propan-2-ol (BAS 750 F) BAS 750 F Solubility in pmm Active without polymer.sup.a) 15 Active with D1 1234 .sup.a)Comparative not according to invention

(22) TABLE-US-00007 TABLE 7 Increased solubility of fenofibrate Fenofibrate Solubility in pmm Active without polymer.sup.a) 0 Active with D1 281 .sup.a)Comparative not according to invention

(23) TABLE-US-00008 TABLE 8 Increased solubility of carbamazepine cabamazepine Solubility in pmm Active without polymer.sup.a) 181 Active with D1 1032 .sup.a)Comparative not according to invention

Application Example 4

Increased Storage Stability of Suspension Concentrate

(24) An aqueous suspension concentrate SC4 was prepared comprising 80 g/l fluxapyroxad, 80 g/l graft polymer (see Table 6), 25 g/l 1,2-propylene glycol, 13 g/L sodium salt of naphthalene sulfonate condensate, 1.5 g/l xanthan gum, 5 g/l anionic phenolsulfonic acid-urea-formaldehyde condensate, silicon defoamer, and antibacterials. For comparison, the aqueous suspension concentrate SC4 was prepared without the addition of any graft polymer (SC4 without graft polymer). The suspension concentrates were stored for 14 days at 20 C. or at 40 C. The stability of the formulation was determined by using instrument Malvern. D90 is the value in m that 90% (volume/volume) of the particles existing in the formulation have a size smaller this value. An increase in D 90 is an indication for the destabilization of SC formulations.

(25) TABLE-US-00009 TABLE 9 Particle size D90 during storage of suspension concentrate SC4 D (90) 0 d 14 d at 20 C. 14 d at 20 C. Reference formulation 2.0 m 2.0 m 2.0 m D1 1.9 m 2.0 m 1.9 m D2 2.0 m 2.0 m 1.9 m Comparison Plurafac LF 300.sup.a) 2.0 m 7.9 7.8 .sup.a)Comparative data Plurafac is a nonionic surfactant based on alkoxylated, prodominantly unbranched falty alcohols, containing higher alkyleneoxide.

(26) The comparative polymer resulted in a clear increase of particle size during storage.