US 12,129,230 B2
Dialkyl carbonate production method
Hongyu Liu, Tokyo (JP); Takehiko Isobe, Tokyo (JP); Yousuke Shinkai, Tokyo (JP); and Hidefumi Harada, Tokyo (JP)
Assigned to MITSUBISHI GAS CHEMICAL COMPANY, INC., Tokyo (JP)
Appl. No. 17/297,610
Filed by MITSUBISHI GAS CHEMICAL COMPANY, INC., Tokyo (JP)
PCT Filed Dec. 4, 2019, PCT No. PCT/JP2019/047310
§ 371(c)(1), (2) Date May 27, 2021,
PCT Pub. No. WO2020/116485, PCT Pub. Date Jun. 11, 2020.
Claims priority of application No. 2018-230256 (JP), filed on Dec. 7, 2018.
Prior Publication US 2022/0009873 A1, Jan. 13, 2022
Int. Cl. C07C 68/04 (2006.01); B01J 23/10 (2006.01)
CPC C07C 68/04 (2013.01) [B01J 23/10 (2013.01)] 10 Claims
 
1. A method for producing a dialkyl carbonate, the method comprising a carbonate ester generation reaction that involves reaction between an alcohol represented by Formula (1) below and carbon dioxide, wherein the carbonate ester generation reaction is conducted in the presence of a carbodiimide compound represented by Formula (2) below, and
wherein the amount of the carbodiimide compound is 0.4-0.6 mole relative to 1.0 mole of the alcohol:
R1—OH  (1)
wherein R1 in Formula (1) above represents an optionally branched and optionally substituted alkyl group with a carbon number of 1-10
R2—N═C═N—R3  (2)
wherein R2 and R3 in Formula (2) above are each independently selected from:
an optionally branched alkyl group with a total carbon number of 1-20 which may be substituted with an amino group which may have one or more alkyl groups with a carbon number of 5 or less;
an optionally branched cycloalkyl group with a carbon number of 1-20; and
an aryl group with a total carbon number of 6-30 which may be substituted with one or more alkyl groups with a carbon number of 12 or less; and wherein a dialkyl carbonate and water are generated and the carbodiimide compound is allowed to react with said water in the carbonate ester generation reaction.