METHOD FOR PRODUCING AN AROMA SUBSTANCE

Abstract

A method of preparing a compound of formula (IV)

##STR00001##

where R.sub.1 is alkyl of 1 to 4 carbon atoms, comprises reacting cyclohexene with hydrogen peroxide and an alcohol R.sub.1OH in the presence of a catalyst comprising a zeolite of framework structure MWW, wherein the framework of the zeolite comprises silicon, titanium, boron, oxygen and hydrogen.

Claims

1-15. (canceled)

16. A method of preparing a compound of formula (IV) ##STR00022## wherein R.sub.1 is alkyl of 1 to 4 carbon atoms, comprising: (i) providing a liquid mixture comprising cyclohexene, an alcohol R.sub.1OH, hydrogen peroxide and optionally a solvent; (ii) reacting the cyclohexene with the hydrogen peroxide and the alcohol R.sub.1OH in the mixture provided as per (i) in the presence of a catalyst comprising a zeolite of framework structure MWW to obtain a mixture comprising the compound of formula (I) ##STR00023## wherein the framework of the zeolite as per (ii) comprises silicon, titanium, boron, oxygen and hydrogen; (iii) separating the compound of formula (I) off from the mixture obtained as per (ii) to obtain a mixture concentrated in respect of the compound of formula (I); (iv) dehydrogenating the formula (I) compound present in the concentrated mixture obtained as per (iii) to obtain a mixture comprising a compound of formula (II) ##STR00024## (v) formylating the formula (II) compound present in the mixture obtained as per (iv) to obtain a mixture comprising the compound of formula (IV).

17. The method according to claim 16, wherein R.sub.1 is methyl or ethyl, preferably methyl.

18. The method according to claim 16, wherein the liquid mixture provided as per (i) has a molar ratio prior to the reaction as per (ii) of cyclohexene:R.sub.1OH in the range from 1:1 to 1:50, preferably from 1:3 to 1:30 and more preferably from 1:5 to 1:10, and a molar ratio prior to the reaction as per (ii) of cyclohexene:hydrogen peroxide in the range from 1:1 to 5:1, preferably from 1.5:1 to 4.5:1, more preferably from 2:1 to 4:1.

19. The method according to claim 16, wherein the liquid mixture provided as per (i) comprises no solvent.

20. The method according to claim 16, wherein the reaction as per (ii) is carried out at a temperature in the range from 40 to 150° C., preferably from 50 to 125° C., more preferably from 70 to 100° C., wherein the duration of the reaction as per (ii) is preferably in the range from 1 to 12 h, more preferably from 1.5 to 10 h, more preferably from 2 to 8 h, and wherein the mass ratio of hydrogen peroxide:zeolite of framework structure MWW at the start of the reaction as per (ii) is preferably in the range from 10:1 to 0.1:1, more preferably from 1:1 to 0.2:1, more preferably from 0.75:1 to 0.25:1.

21. The method according to claim 16, wherein not less than 99 wt %, preferably not less than 99.5 wt %, more preferably not less than 99.9 wt % of the framework of the zeolite as per (ii) consists of silicon, titanium, boron, oxygen and hydrogen, and wherein, in the zeolite of framework structure MWW, the molar ratio of B:Si is preferably in the range from 0.02:1 to 0.5:1, more preferably from 0.05:1 to 0.15:1, and the molar ratio of Ti:Si is preferably in the range from 0.01:1 to 0.05:1, more preferably from 0.017:1 to 0.025:1, while the zeolite of framework structure MWW is preferably obtained as per a method comprising: (a) providing an aqueous synthesis mixture comprising a silicon source, a boron source, a titanium source and an MWW-templating compound, wherein the temperature of the aqueous synthesis mixture is not more than 50° C.; (b) heating the aqueous synthesis mixture provided as per (a) from the temperature of not more than 50° C. to a temperature in the range from 160 to 190° C. in the course of a period of at most 24 h; (c) subjecting the synthesis mixture as per (b) to hydrothermal synthesis conditions under autogenous pressure in a closed system at a temperature in the range from 160 to 190° C. to obtain a precursor to the zeolite of framework structure MWW in its mother liquor; (d) separating the precursor to the zeolite of framework structure MWW off from its mother liquor; and (e) calcining the MWW framework structure zeolite precursor separated off as per (d) to obtain the zeolite of framework structure MWW.

22. The method according to claim 16, wherein the mole percentage for the compound of formula (I) in the mixture obtained from the reaction as per (ii), based on the sum total of mole percentages for the compounds of formulae (I), (Ib), (Ic), (Id) and (Ie) ##STR00025## in the mixture obtained from the reaction as per (ii) is not less than 85%, preferably not less than 90%.

23. The method according to claim 16, wherein as per (iii) the step of separating the compound of formula (I) off from the mixture obtained as per (ii) comprises a distillation, wherein the mixture obtained from the distillation and concentrated in respect of the compound of formula (I) comprises the compound of formula (I) at preferably not less than 90 wt %, more preferably at not less than 95 wt %, more preferably at more than 95 wt %.

24. The method according to claim 16, wherein the mixture obtained as per (iii), concentrated in respect of the compound of formula (I), is vaporized, preferably at a temperature in the range from 175 to 375° C., more preferably from 225 to 325° C., more preferably from 250 to 300° C., prior to the dehydrogenation as per (iv).

25. The method according to claim 16, wherein the dehydrogenation as per (iv) is carried out in the presence of a heterogeneous catalyst, wherein the catalyst preferably comprises a noble metal selected from the group consisting of Pd, Rh, Pt and a combination of two or more thereof, wherein the noble metal is preferably supported by one or more than one carrier material, which is preferably selected from the group consisting of activated carbon, aluminum oxide, silicon oxide and a combination of two or more thereof, wherein the catalyst more preferably comprises palladium as noble metal and activated carbon as carrier material, and wherein the dehydrogenation as per (iv) is carried out at a catalyst temperature, preferably, in the range from 200 to 400° C., more preferably from 250 to 350° C., more preferably from 275 to 325° C.

26. The method according to claim 16, wherein the formylating step as per (v) is preceded by the compound of formula (II) being separated off from the mixture obtained from (iv) to obtain a mixture concentrated in respect of the compound of formula (II), wherein the step of separating off preferably comprises a distillation, wherein the mixture obtained, which is concentrated in respect of the compound of formula (II), comprises the compound of formula (II) at preferably not less than 95 wt %, more preferably at not less than 98 wt %.

27. The method according to claim 16, wherein the formylating step as per (v) comprises: (v-1) reacting the formula (II) compound present in the mixture obtained as per (iv) with glyoxylic acid OHC—COOH, preferably in aqueous phase, to obtain a mixture comprising a compound of formula (III) ##STR00026## (v-2) preferentially purifying the mixture obtained as per (v-1) in respect of the compound of formula (III) to obtain a preferably aqueous mixture comprising the compound of formula (III), wherein the step of purifying preferably comprises an extraction; (v-3) oxidatively decarboxylating the formula (III) compound present in the mixture obtained as per (v-1), preferably as per (v-2), to obtain a mixture comprising the compound of formula (IV).

28. The method according to claim 27, wherein the step of reacting as per (v-1) is carried out in the presence of a Bronstedt base, preferably selected from the group consisting of alkali metal hydroxides, alkaline earth metal hydroxides and a mixture of two or more thereof, more preferably from the group consisting of alkali metal hydroxides and a mixture of two or more thereof, more preferably in the presence of sodium hydroxide, wherein the step of reacting as per (v-1) is carried out at a temperature preferably in the range from 10 to 40° C., more preferably in the range from 15 to 35° C., more preferably in the range from 20 to 30° C.

29. The method according to claim 27, wherein the step of oxidatively decarboxylating as per (v-3) is carried out in the presence of an oxidizing agent selected from the group consisting of CuO, PbO.sub.2, MnO.sub.2, Co.sub.3O.sub.4, HgO, Ag.sub.2O, Cu(II) salts, Hg(II) salts, Fe(III) salts, Ni(III) salts, Co(III) salts, chlorates and a mixture of two or more thereof, preferably from the group consisting of CuO, MnO.sub.2, Cu(II) salts, Fe(III) salts and a mixture of two or more thereof, more preferably in the presence of FeCl.sub.3, wherein the step of oxidatively decarboxylating as per (v-3) is carried out at a temperature preferably in the range from 60 to 110° C., more preferably from 70 to 100° C., more preferably from 80 to 95° C.

30. The method according to claim 16, comprising: (vi) separating the compound of formula (IV) off from the mixture obtained as per (v), preferably from the mixture obtained as per (v-3); wherein the mixture obtained as per (v), preferably as per (v-3), preferably comprises water and one or more than one organic solvent, and wherein (vi) preferably comprises: (vi-1) separating the organic phase from the aqueous phase to obtain an organic phase comprising the compound of formula (IV); (vi-2) optionally extracting the aqueous phase with one or more than one organic solvent to obtain one or more than one further organic phase comprising the compound of formula (IV); (vi-3) preferably washing the organic phase or phases comprising the compound of formula (IV) and obtained as per (vi-1) or, respectively, as per (vi-1) and (vi-2); (vi-4) concentrating the organic phase obtained as per (vi-1) or the organic phases obtained as per (vi-1) and (vi-2), preferably the organic phase washed as per (vi-3) or the organic phase washed as per (vi-3), in respect of the compound of formula (IV), preferably under reduced pressure compared with ambient pressure.

Description

SHORT DESCRIPTION OF FIGURES

[0291] FIG. 1 shows the .sup.11B solid state NMR spectrum of the zeolite according to Example 1, as measured according to Reference Example 1. The .sup.11B chemical shift (in ppm) is shown on the x-axis, while the intensity (*10.sup.6) is shown on the y-axis. The scale divisions on the x-axis are, from left to right, at 40, 20, 0, −20. The scale divisions on the y-axis are, from bottom to top, at 0, 1, 2, 3, 4.

[0292] FIG. 2 shows the .sup.29Si solid state NMR spectrum of the zeolite according to Example 1, as measured according to Reference Example 2. The .sup.29Si chemical shift (in ppm) is shown on the x-axis, while the intensity (*10.sup.6) is shown on the y-axis. The scale divisions on the x-axis are, from left to right, at −90, −100, −110, −120, −130. The scale divisions on the y-axis are, from bottom to top, at 0, 20, 40, 60, 80, 100.

[0293] FIG. 3 shows the FT-IR spectrum of the zeolite according to Example 1, as measured according to Reference Example 4. The wavelength (in cm.sup.−1) is shown on the x-axis and the extinction is shown on the y-axis. The scale divisions on the x-axis are, from left to right, at 4000, 3500, 3000, 2500, 2000, 1500. The scale divisions on the y-axis are, from bottom to top, at 0.00, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, The wavenumbers indicated on the individual peaks in cm.sup.−1 are, from left to right, 3748, 3719, 3689, 3623, 3601, 3536, 1872.

[0294] FIG. 4 shows the x-ray diffraction pattern (copper K-alpha radiation) of the zeolite according to Example 1, measured according to Reference Example 5. The degree values (2 theta) are shown on the x-axis and the intensity (Lin (counts)) are shown on the y-axis. The scale divisions on the x-axis are, from left to right, at 2, 10, 20, 30, 40, 50, 60, and 70. The scale divisions on the y-axis are, from bottom to top, at 0 and 3557

LITERATURE CITED

[0295] GB 2 252 556 A [0296] A. Corma et al., “Activity of Ti-Beta Catalyst for the Selective Oxidation of Alkenes and Alkanes”, Journal of Catalyis (1994), vol. 145, pp. 151-158 [0297] Y. Goa et al., “Catalytic Performance of [Ti, Al]-Beta in the Alkene Epoxidation Controlled by the Postsynthetic Ion Exchange”, Journal of Physical Chemistry B 2004, vol. 108, pp. 8401-8411 [0298] E. G. Derouane et al., “Titanium-substituted zeolite beta: an efficient catalyst in the oxy-functionalisation of cyclic alkenes using hydrogen peroxide in organic solvents”, New. J. Chem., 1998, pp. 797-799 [0299] M. A. Uguina et al., J. Chem. Soc., Chem. Commun., 1994, p. 27