Continuous method for preparing carbonate esters

Patent metadata

Field	Value
Publication number	US-11028065-B1
Application number	US-202016812628-A
Country	US
Kind code	B1
Filing date	Mar 9, 2020
Priority date	Mar 9, 2020
Publication date	Jun 8, 2021
Grant date	Jun 8, 2021

Abstract

In one embodiment, a continuous process for preparing organic carbonate solvent of Formula (I) as described herein comprises contacting a first reactant (an alcohol) with a reactive carbonyl source (carbonyldiimidazole (CDI) or an alkylchloroformate) in the presence of a catalyst in reaction stream flowing through a continuous flow reactor at temperature 20° C. to about 160° C. and at a flow rate providing a residence time in the range of about 0.1 minute to about 24 hours; collecting a reactor effluent exiting from the continuous flow reactor; recovering a crude product from the reactor effluent; and distilling the crude product to obtain the organic carbonate compound of Formula (I). In another embodiment, the first reactant is an epoxide and the carbonyl source is carbon dioxide.

First claim

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A continuous processes for preparing an organic carbonate solvent of Formula (I):

comprising the steps of:
(a) contacting a first reactant with a reactive carbonyl source in reaction stream containing a catalyst flowing through a continuous flow reactor at a temperature in the range of about 20° C. to about 160° C., and at a flow rate providing a residence time in the range of about 0.1 minute to about 24 hours;
(b) optionally quenching any remaining reactive carbonyl source;
(c) collecting a reactor effluent exiting from the continuous flow reactor;
(d) recovering a crude product from the reactor effluent; and
(e) purifying the crude product to obtain the organic carbonate compound of Formula (I);
wherein:
Z is a covalent bond;
x is 0;
R is C 1 -C 6 alkyl or C 1 -C 6 fluoroalkyl bearing at least one fluoro substituent;
R 2 is H, C 1 -C 6 alkyl or C 1 -C 6 fluoroalkyl bearing at least one fluoro substituent;
both R 3 and R 4 are CH 2 and are not directly bonded together;
R and R′ independently are C 1 -C 6 alkyl or C 1 -C 6 fluoroalkyl comprising at least one fluoro substituent;
and wherein the first reactant is an alcohol of Formula (II):

the carbonyl source is a chloroformate of formula Cl(CO)OCH 2 R′; the catalyst is selected from the group consisting of a tertiary amine, an aromatic nitrogen-containing heterocycle, and quaternary ammonium hydroxide, the catalyst is present in the reaction stream at a concentration of about 100 to 150 mol % relative to the alcohol; and the reaction stream comprises an aprotic organic solvent selected from the groups consisting of a nitrile, a glycol ether, and ketone in which the alcohol, the chloroformate, and the catalyst are dissolved.

2. The process of claim 1 , wherein the alcohol is dissolved in the solvent at a concentration of about 0.5 to about 6 molar (M).

3. The process of claim 1 , wherein the solvent comprises acetonitrile.

4. The process of claim 1 , wherein the catalyst comprises diisopropylethylamine.

5. The process of claim 4 , wherein the alcohol is 2,2,2-trifluoroethanol; the carbonyl source is methylchloroformate; the catalyst is diisopropylethylamine; the solvent is acetonitrile; the alcohol is dissolved in the solvent at a concentration of about 0.5 to 6 M; and the continuous flow reactor is heated at a temperature in the range of about 30° C. to about 110° C.

6. A continuous processes for preparing an organic carbonate solvent of Formula (I):

comprising the steps of:
(a) contacting a first reactant with a reactive carbonyl source in reaction stream containing a catalyst flowing through a continuous flow reactor at a temperature in the range of about 20° C. to about 160° C., and at a flow rate providing a residence time in the range of about 0.1 minute to about 24 hours;
(b) optionally quenching any remaining reactive carbonyl source;
(c) collecting a reactor effluent exiting from the continuous flow reactor;
(d) recovering a crude product from the reactor effluent; and
(e) purifying the crude product to obtain the organic carbonate compound of Formula (I);
wherein:
Z is a covalent bond;
x is 0;
R 1 is C 1 -C 6 alkyl or C 1 -C 6 fluoroalkyl bearing at least one fluoro substituent;
R 2 is H, C 1 -C 6 alkyl or C 1 -C 6 fluoroalkyl bearing at least one fluoro substituent;
both R 3 and R 4 are CH 2 and are not directly bonded together;
R is C 1 -C 6 alkyl or C 1 -C 6 fluoroalkyl comprising at least one fluoro substituent;
and wherein the first reactant is an alcohol of Formula (II):

the carbonyl source is carbonyldiimidazole (CDI); the catalyst is selected from the group consisting tertiary amine, an aromatic nitrogen-containing heterocycle, and a quaternary ammonium hydroxide; the catalyst is present in the reaction stream at a concentration of about 2 to 15 mol % relative to the alcohol; and the reaction stream comprises an aprotic organic solvent selected from the group consisting of a nitrile, an ester, an organic carbonate ester, an amide, a ketone, a sulfone, a sulfoxide, a halogenated hydrocarbon, a phosphoramide, and an ionic liquid, in which the alcohol, the CDI, and the catalyst are dissolved.

7. The process of claim 6 , wherein the alcohol is 2,2,2-trifluoroethanol.

8. The process of claim 6 , wherein the solvent comprises dimethylformamide.

9. The process of claim 6 , wherein the alcohol is present in the reaction stream in a respective molar ratio of alcohol-to-CDI of about 1.8:1 to about 2.6:1.

10. The process of claim 6 , wherein the alcohol is 2,2,2-trifluoroethanol; the solvent is selected from the group consisting of dimethylformamide, acetonitrile, acetone, and dimethylsulfoxide; the alcohol is present in the reaction stream in a respective molar ratio of alcohol to CDI of about 2:1 to about 3:1; and the continuous flow reactor is heated at a temperature in the range of about 50 to about 120° C.

11. The process of claim 1 , wherein the first reactant is the epoxide of Formula (III); the carbonyl source is carbon dioxide; the catalyst is selected from the group consisting of an acid addition salt of a bicyclic amidine, an acid addition salt of a phosphazene, an acid addition salt of a bicyclic guanidine, a quaternary ammonium halide, and a quaternary phosphonium halide; the catalyst is present in the reaction stream at a concentration of about 1 to 20 mol % relative to the epoxide; the carbon dioxide is present in the reaction stream at a pressure in the range of about 1 to about 10 bar; and the reaction stream comprises an aprotic organic solvent selected from the group consisting of a nitrile, an ester, an organic carbonate ester, an amide, a ketone, a sulfone, a sulfoxide, and a halogenated hydrocarbon and wherein the epoxide is 3,3,3,-trifluoropropylene-1,2-oxide.

12. The process of claim 11 , wherein the reaction stream flowing through the continuous flow reactor is heated at a temperature in the range of about 50° C. to about 120° C.

13. The process of claim 11 , wherein the solvent comprises acetonitrile.

14. The process of claim 11 , wherein the solvent is acetonitrile; the catalyst is selected from the group consisting of tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium iodide, and benzyltriethylammonium bromide; the catalyst is present at a concentration of about 1 to about 15 mol % relative to the epoxide; and the continuous flow reactor is heated at a temperature in the range of about 50° C. to about 120° C.

Assignees

• Uchicago Argonne Llc

Inventors

• Dzwiniel Trevor L
• Pupek Krzysztof

Classifications

• B01J31/0244

  with nitrogen contained as ring member in aromatic compounds or moieties, e.g. pyridine · CPC title

• B01J31/0239

  Quaternary ammonium compounds · CPC title

• B01J31/0237

  Amines · CPC title

• C07C68/02

  from phosgene or haloformates · CPC title

• C07C68/00

  Preparation of esters of carbonic or haloformic acids · CPC title