Patent ID: 8889882

Claim:
A process for preparing a compound of formula III: or a salt thereof; where R 1 is —C 1-6 alkyl; R 2 is —O—C 1-5 alkyl; R 3 is —C 1-6 alkyl, —C 0-3 alkylenearyl, —C 0-3 alkyleneheteroaryl, or —C 0-3 alkylene-C 3-7 cycloalkyl; and R 4 is —C 1-6 alkyl, —C 0-6 alkylene-C 3-7 cycloalkyl, —C 0-6 alkylenearyl, or —C 0-6 alkylenemorpholine; the process comprising the steps of: (a) reacting a compound of formula I: with a potassium-C 1-6 alkyl-trifluoroborate reagent in the presence of a palladium-phosphine catalyst to form a compound of formula 3: where P is a carboxylic acid protecting group; (b) reacting the compound of formula 3 with hydroxylamine or a salt thereof to form a compound of formula 4: (c) reacting the compound of formula 4 with a reducing agent to form a compound of formula II: or a salt thereof; (d) reacting the compound of formula II or a salt thereof with a compound of formula 5: or a salt thereof, in the presence of an amine-carboxylic acid coupling reagent to form a compound of formula 6: or a salt thereof; and (e) removing the carboxylic acid protecting group, P, from the compound of formula 6 or a salt thereof, to form a compound of formula III or a salt thereof.