Ethanone, 1-cyclopropyl

A soln. of l-/ r/-butyldimethylsilyl-2-chloro-l-ethanone in THF added dropwise during 15 min to a stirred soln. of Li-2,2,6,6-tetramethylpiperidide in the same solvent at —78° under argon, after 30 min methyl vinyl ketone added, the mixture allowed to warm to room temp, during 1 h, and half-satd. NH4CI soln. added after a further 30 min-> l-[2-(/er/-butyldimethylsilyloxomethyl)cyclopropyl]ethan-l-one. Y 75-89% cis Jrans 1.9 1). F.e., also from a-sulfonioacylsilanes, s. J.S. Nowick, R.L. Danheiser, Tetrahedron 44, 4113-34 (1988). 

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