N-Ylide Mediated Synthesis and Resolution of a Chiral Pyrimidinyl Cyclopropane Carboxylic Acid

High Resolution Image Download MS PowerPoint Slide We report the synthesis of a pyrimidinyl trans -cyclopropane carboxylic acid (rac- 1 ) in 3 steps (58% yield) from 2-chloro-4-methylpyrimidine ( 2 ), and its chiral resolution via recrystallization of the ( S )-1-(1-naphthyl)ethylamine or (+)-abietylamine salts. Following the observation of a palladium-catalyzed conjugate addition of potassium vinyltrifluoroborate to 4-methyl-2-vinylpyrimidine ( 3 ), an efficient, novel cyclopropanation of 3 was developed through reaction with the nitrogen ylide derived from t -butyl bromoacetate and DABCO.