Process for converting alkylfurans into alcohols and ketones

Abstract

Process for converting alkylfurans to alcohols and ketones. The present invention relates to a process for preparing a compound of formula (I) and / or formula (I'), comprising the following steps: i) contacting a compound of formula (II): in which R2, R3, R4, and R5 are each independently selected from H, methyl, and ethyl, and a metallic hydrogenation / hydrogenolysis catalyst, this contacting being carried out in a reaction medium heated to a temperature T1 greater than or equal to 90 °C and pressurized to a partial pressure PH2 of dihydrogen greater than or equal to 0.01 bar, and ii) forming a compound of formula (I) and / or a compound of formula (I'): R2, R3, R4, and R5 being such as in the compound of formula (II). Figure for abstract: None

Description

98 99 99 100 Composition of the reaction crude 2-Hexanol + 2-He xanone (mol%) 94 95 95 97 2-Hexanol: 2-He xanone (mol%) 13:81 19:76 19:76 1:96 DMTHF (mol%) 4 4 4 2 Hexane (mol%) - - - 1 Hexene (mol%) - - - -

[0149] A short reaction time and a slight increase in reaction temperature makes it possible to obtain a mixture consisting almost exclusively of 2-hexanone.

Claims

Demands

1. A process for preparing a compound of formula (I) and / or of formula (I'), comprising the following steps: i) contacting a compound of formula (II): in which R2, R3, R4 and R5 are each independently selected from H, methyl and ethyl, and a metal hydrogenation / hydrogenolysis catalyst, this contacting being carried out in a reaction medium heated to a temperature T1 greater than or equal to 90 °C and pressurized to a partial pressure PH2 of dihydrogen greater than or equal to 0.01 bar, and ii) forming a compound of formula (I) and / or a compound of formula (I'): R2, R3, R4 and R5 being such as in the compound of formula (II).

2. A method according to claim 1, wherein the temperature Tl ranges from 90°C to 300°C, preferably from 110°C to 260°C, preferably from 130°C to 240°C, preferably from 140°C to 230°C, preferably from 150°C to 220°C, preferably from 160°C to 210°C, preferably from 170°C to 210°C.

3. A method according to claim 1 or 2, wherein the hydrogen pressure PH2 ranges from 0.1 bar to 20 bar, preferably from 0.5 bar to 15 bar, preferably from 1.0 bar to 12 bar, preferably from 2.0 bar to 10 bar, preferably from 3.0 bar to 8.0 bar, preferably from 3.0 bar to 5.0 bar.

4. A method according to any one of the preceding claims, wherein the metal hydrogenation / hydrogenolysis catalyst comprises at least one metal selected from Re, Cu, Fe, Ru, Os, Ir, Co, Rh, Pt, Pd, and Ni, more preferably chosen from Ru, Rh, Pt and Pd, advantageously is platinum; and preferably is supported on a support chosen from carbon supports.

5. A process according to any one of the preceding claims, wherein the metal hydrogenation / hydrogenolysis catalyst is supported, and has a dispersion of the metal on the support ranging from 1.2% to 90%, preferably from 2.0% to 75%, preferably from 2.5% to 50%, preferably from 3.0% to 20%, preferably from 3.0% to 15%, preferably from 3.5% to 12%, preferably between 3.8% and 10%.

6. A process according to any one of the preceding claims, comprising the following steps: a) the preparation of a reaction medium heated to a temperature Tl greater than or equal to 90 °C and pressurized to a partial pressure PH2 of dihydrogen greater than or equal to 0.01 bar, the reaction medium comprising a metal hydrogenation / hydrogenolysis catalyst and optionally a solvent, and obtaining a heated and pressurized reaction medium, b) the introduction of the compound of formula (II) into the heated and pressurized reaction medium obtained in step a), optionally mixed with a solvent, and c) the formation of the compound of formula (I) and / or the compound of formula (I').

7. A process according to any one of claims 1 to 5, comprising the following steps: a') the preparation of a reaction medium heated to a temperature Tl greater than or equal to 90 °C and pressurized to a partial pressure Ph2 of dihydrogen greater than or equal to 0.01 bar, the reaction medium comprising a solvent and the compound of formula (II), and obtaining a heated and pressurized reaction medium, b') the introduction of the metal hydrogenation / hydrogenolysis catalyst, optionally in solution or in suspension in a solvent, into the heated and pressurized reaction medium obtained in step a), and c') the formation of the compound of formula (I) and / or the compound of formula (I').

8. A process according to claim 6 or 7, wherein the solvent is selected from C6-C20 alkanes, C1-C10 alcohols, and C3-C10 ketones, preferably from linear alkanes in C6-20, primary or secondary and linear alcohols in C3-C10 preferably in C3-C6, and linear alkanones in C3-C10 preferably in C3-C6, or any mixture thereof; advantageously is dodecane, hexadecane, 2-hexanol, 2-hexanone or a mixture of 2-hexanol and 2-hexanone or a mixture of 2-pentanol and 2-pentanone.

9. A process according to any one of the preceding claims, wherein the metal hydrogenation / hydrogenolysis catalyst is supported, and has a dispersion of the metal on the support ranging from 2.0% to 9.0%, preferably from 2.5% to 8.0%, preferably from 3.0% to 7.0%, preferably between 3.5% and 6.0%, preferably between 4.0% and 5.0%.

10. A process according to any one of the preceding claims, wherein the partial pressure of dihydrogen is maintained constant at the value (PH2) during the implementation of the process, in particular during step ii), or c) or c').

11. A process according to any one of the preceding claims, comprising the following steps: A) steps i) and ii) according to any one of claims 1 to 5, 9 and 10, or steps a), b) and c) according to any one of claims 6, 9 and 10, or steps a'), b') and c') according to any one of claims 7 to 10, step ii), c) or c') forming a mixture of compound of formula (I) and compound of formula (!'), and B) a step d) of hydrogenating the compound of formula (!') present in the mixture from step ii) or c) or c').

12. A process according to claim 11, wherein step d) is carried out in the presence of a metallic hydrogenation catalyst having a higher catalytic power of hydrogenation of a C=O bond than that of the metallic hydrogenation / hydrogenolysis catalyst of step i) or a) or b'), preferably comprising ruthenium.

13. A method according to claim 11 or 12, wherein step d) is carried out at a temperature T2 between 40°C and 150°C, preferably between 60°C and 120°C, preferably between 70°C and 90°C.

14. A process according to any one of claims 1 to 8, wherein the metal hydrogenation / hydrogenolysis catalyst is supported, and exhibits a dispersion of the metal on the support ranging from 4.0% to 40%, preferably from 6.0% to 20%, preferably from 7.0% to 23 15%, preferably between 8.0% and 12%, preferably between 9.0% and 10%.

15. A method according to any one of claims 1 to 8 or 14, wherein the temperature Tl ranges from 190°C to 220°C, preferably from 190°C to 210°C.