Patent ID: 8143427

Claim:
A method for producing an aminoacetylpyrrolidinecarbonitrile derivative represented by the formula (2): comprising allowing an acid to act on an aminoacetylpyrrolidinecarboxamide derivative represented by the formula (1) to form a salt wherein A represents CH 2 , CHF or CF 2 ; and R 1 represents a secondary amino group of the formula (3): R 2 —NH— (3) wherein R 2 represents a C 1 -C 6 alkyl group which may be substituted, a C 3 -C 10 cyclic alkyl group which may be substituted or a C 2 -C 10 cyclic amino group which may be substituted, and the substituents for the C 1 -C 6 alkyl group, C 3 -C 10 cyclic alkyl group and C 2 -C 10 cyclic amino group are selected from a halogen atom, a hydroxyl group, a cyano group, a C 1 -C 6 alkoxy group, an aryloxy group which may be substituted, a C 1 -C 6 alkylcarbonyl group, a C 1 -C 6 alkoxycarbonyl group, a C 1 -C 6 alkylthio group, an amino group, a mono- or di-substituted C 1 -C 6 alkylamino group, a 4- to 9-membered cyclic amino group which may contain 1 to 3 hetero atoms, a formylamino group, a C 1 -C 6 alkylcarbonylamino group, a C 1 -C 6 alkoxycarbonylamino group, a C 1 -C 6 alkylsulfonylamino group, and an arylsulfonylamino group which may be substituted; and then allowing a dehydrating agent to act on the salt, wherein the acid is a trihalogenoacetic acid, an arylsulfonic acid which may be substituted or a C 1 -C 3 alkylsulfonic acid which may be substituted with one or more halogen atom(s).