Ethyl diazoacetate → ethyl (1R,2R)-2-(4-bromophenyl)cyclopropanecarboxylate

Participants

Reaction Conditions

Reaction Steps

Copper(II) acetylacetonate (0.156 g, 0.6 mmol) was dissolved in CH2Cl2 (40 mL) then phenylhydrazine (3 drops, catalytic amount) was added. After 5 minutes, 4-bromostyrene (2.6 mL, 20 mmol) was added and the reaction was heated to 40° C. Ethyl diazoacetate (3.1 mL, 30 mmol) in CH2Cl2 (40 mL) was slowly added using a syringe pump. The reaction was stirred at 40° C. overnight then cooled and submitted to standard aqueous workup. The crude material was purified on silica gel (0-10% EtOAc in hexanes) two times to afford a separable mixture of two cyclopropyl isomers (cis- and trans-) and the less polar isomer was determined to be the title compound.

Provenance & Evidence