Patent ID: 6806381
Filing Date: 2004-10-19
Classification: C07C

Abstract:
A process for synthesizing a compound of formula I wherein R1 represents halogen, trifluoromethyl, an alkyl group of 1 to 6 carbons, or a cycloalkyl group of 3 to 7 carbons; R2 and R5 are the same or different and represent hydrogen, halogen, an alkyl group of 1 to 4 carbons, or a cycloalkyl group of 3 to 6 carbons, at least one of R2 and R3 being other than, hydrogen; R4 represents hydrogen or a lower alkyl group; R5 represents a carboxylic acid or an alkyl ester thereof; and Y represents â€”(CH2)nâ€”where n is an integer from 1 to 5, or a cis- or trans-ethylene group â€”CH=CHâ€”; and all stereoisomers thereof; said process comprising the steps of: a) reacting a compound of formula III with a phenol of formula A, wherein R1, R2, R3, and R4 are as defined above and G is a protecting group, in the presence of a base to produce a compound of formula IV; b) deprotecting and reducing the compound of formula IV to form a compound of formula VI; c) reacting the compound of formula VI with a compound of the formula XC(O)YR5, wherein X represents OH or a halogen and R5 is a carboxylic acid alkyl ester, in the presence of a base, to produce a compound of formula I wherein R5 is a carboxylic acid alkyl ester; and (d) optionally de-esterifying the compound of formula I wherein R5 is a carboxylic acid alkyl ester to produce a compound of formula I wherein R5 is a carboxylic acid; wherein the compound of Formula III is produced by reacting a compound of formula II wherein L is a leaving group; R2 and R3 are the same or different and represent hydrogen, halogen, an alkyl group of 1 to 4 carbons, or a cycloalkyl group of 3 to 6 carbons, at least one of R2 and R3 being other than hydrogen; and R4 alkyl group; with an iodinating agent.