Remarkable Dependence of Diastereoselectivity on Anhydrous or Aqueous Solvent in the Indium Hydride Promoted Reductive Aldol Reaction of α,β-Unsaturated Ketones
作者:Katsuyuki Inoue、Tatsuya Ishida、Ikuya Shibata、Akio Baba
Dichloroindium hydride generated by the transmetallation between tributyltin hydride and indium trichloride predominantly reduced α,β-unsaturated ketones (enones) with 1,4-selectively even in the presence of aldehydes. Under anhydrous conditions, the successive aldolreaction between the resulting enolates and the remaining aldehydes proceeded with high anti-selectivity. The stereochemistry was dramatically
A catalytic amount of In(OAc) 3 smoothly promoted 1,4-reduction of certain α-enones with PhSiH 3 in ethanol at ambient temperature. The intermediary enolates could be used for inter- and intramolecular aldol reactions andintramolecular Michael addition.