Nucleophilic cyclopropanation reaction with bis(iodozincio)methane by 1,4-addition to alpha,beta-unsaturated carbonyl compounds.
Treatment of alpha,beta-unsaturated ketones with an electrophilic site at the gamma-position in the presence of trimethylsilyl cyanide with bis(iodozincio)methane afforded the (Z)-silyl enol ether of the beta-cyclopropyl substituted ketone in good yields. The reaction proceeds by 1,4-addition to form an enolate, and its sequential intramolecular nucleophilic attack to an adjacent electrophilic site. The reaction of gamma-ethoxycarbonyl-alpha,beta-unsaturated ketone and bis(iodozincio)methane in the presence of trimethylsilyl cyanide afforded 1-ethoxy-1-trimethylsiloxycyclopropane derivatives, which can be regarded as the homoenolate equivalent. Additionally, reaction of the obtained homoenolate equivalents with imines give 1-(E)-alkenyl-2-(1-aminoalkyl)alkanols diastereoselectively.
Nomura
Kenichi
K
Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoutodaigaku-katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
Hirayama
Takaharu
T
Matsubara
Seijiro
S