Water → trans-2-(3-Fluoro-phenyl)-cyclopropanecarboxylic acid

Participants

Reaction Steps

To a solution of rac-trans 2-(3-fluoro-phenyl)-cyclopropanecarboxylic acid ethyl ester (13.0 g, 0.062 mol) in MeOH (310 mL) was added a solution of KOH (35.0 g, 0.625 mol) in MeOH (150 mL) at 0° C. After addition of the base the reaction mixture was stirred at room temperature for 18 h. The reaction mixture was poured into water and extracted with methylene chloride (2×50 mL). The aqueous layer was acidified with 10% HCl. The resulting mixture was extracted with methylene chloride (2×150 mL). The combined organic layers were dried over Na2SO4 and evaporated to dryness to give rac-trans-2-(3-fluoro-phenyl)-cyclopropanecarboxylic acid as colorless crystals (9.5 g, 85%). Separation of the isomers by chiral SFC (Method D) gave the title compound (1S,2S)-2-(3-fluoro-phenyl)cyclopropanecarboxylic acid IM47 as colorless crystals (3.27 g, 17% overall yield from 3-fluorostyrene) sufficiently pure for the next step. Specific optical rotation +263.4° [α]D20 (C=1% MeOH)

Provenance & Evidence