Bicyclo[2.2.1]heptane-1-methanesulfonic acid, 7,7-dimethyl-2-oxo-, (1S)- → methyl N-{(4-bromophenyl)[4-(methylsulfonyl)phenyl]methylene}leucinate

Participants

Reaction Steps

A solution of (4-bromophenyl)[4-(methylsulfonyl)phenyl]methanone (202 mg, 0.59 mmol), L-leucine methyl ester hydrochloride (328 mg, 2.0 mmol) and camphor sulfonic acid (52 mg, 0.22 mmol) in toluene was refluxed for 18 hours using a Dean-Stark trap. The solvent was removed in vacuo and the resulting residue was purified by chromatography using EtOAc and hexane as eluant to give a 1:1 mixture of the title compound and the starting (4-bromophenyl)[4-(methylsulfonyl)phenyl]methanone.

Provenance & Evidence