Process for producing hexahydrothieno (3,4-D)immidazole-2,4-diones
AssigneeSumitomo Chemical Company, Limited
InventorsToshitsugi Uemura, Mamoru Shirahata, Yasunobu Miyamoto
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Abstract
There is disclosed a process for producing hexahydrothieno[3,4-d]imidazole-2,4-diones of formula (1): wherein R1 and R2 are the same or different and independently represent a hydrogen atom, a lower alkyl, alkenyl, aryl or aralkyl group all of which may be substituted, which is characterized by reacting hexahydrofuro[3,4-d]imidazole-2,4-diones of formula (2): wherein R1 and R2 are the same as defined above, with thioamide in the presence of alkali hydrogen sulfide, sulfur and a basic compound selected from alkali metal carbonate, alkali metal sulfide, an alkali metal salt of the carboxylic acid having C2-C6 carbon atoms and an organic base having C6-C10 carbon atoms.
Claims19
A process for producing a hexahydrothieno[3,4-d]imidazole-2,4-dione of formula (1):
- wherein R1 and R2 are the same or different and independently represent a hydrogen atom, a lower alkyl group, an alkenyl group, an aryl group or an aralkyl group all of which may be substituted, which comprises:
- reacting a hexahydrofuro[3,4-d]imidazole-2,4-dione of formula (2):
- wherein R1 and R2 are the same as defined above with a thioamide in the presence of an alkali hydrogen sulfide, sulfur and a basic compound selected from an alkali metal carbonate, an alkali metal salt of the carboxylic acid having C2-C6 carbon atoms and an organic base having C6-C10 carbon atoms, wherein the total amount of thioamide, alkali hydrogen sulfide and sulfur is 1.5 moles or less per mol of the compound of formula (2).
A process for producing a compound of formula (1):
- wherein R1 and R2 are the same or different and independently represent a hydrogen atom, a lower alkyl group, an alkenyl group, an aryl group or an aralkyl group, all of which may be substituted, said method comprising:
- reacting a compound of formula (2):
- with a thioamide in the presence of
- (A) an alkali hydrogen sulfide,
- (B) sulfur, and
- (C) a basic compound selected from the group consisting of
- (1) an alkali metal carbonate,
- (2) an alkali metal salt of the carboxylic acid having C2-C6 carbon atoms, and
- (3) an organic base having C6-C10 carbon atoms,
- wherein the amount of thioamide is 0.1 mole or more per mole of the compound of formula 2;
- wherein the amount of alkali hydrogen sulfide is 0.1 mole or more per mole of the compound of formula 2;
- wherein the amount of sulfur is at least 0.1 mole per mole of the compound of formula 2;
- wherein the amount of basic compound is 0.02 to 2 moles per mole of the compound of formula 2;
- and
- wherein the total amount of thioamide, alkali hydrogen sulfide and sulfur is 0.9 to 2.0 moles per mol of the compound of formula (2).
Dependencies are inferred from the claim text.