Patent ID: 9346763
Filing Date: 2016-05-24
CPC Classification: C07C,C07D,Y02P

Claim Text:
1. Process for the preparation of a pyrazole carboxylic acid derivative of the formula wherein R a) reacting an oxoacetate of the formula wherein R wherein R wherein R b) coupling the aminomethylene succinic acid ester of the formula IV with an N-protected hydrazine derivative of formula wherein R wherein R c) ring closing the hydrazinomethylene succinic acid ester of formula VI under acidic conditions to form the pyrazole dicarboxylic acid ester of the formula wherein R d) hydrolyzing the pyrazole dicarboxylic acid ester of the formula VII in 3-position with a base to form the pyrazole carboxylic acid derivative of the formula I.