Zn-induced allylation of chromone-3-carbaldehyde 1 produces 3-(1-hydroxy-3-butene-1-yl)chromone 2, which gives back 1 on treatment with formalin under acidic conditions, and reacts differently towards nitrogenous nucleophiles.
Optically active uracil and chromen-4-one substituted homoallylic alcohols were obtained from the corresponding racemic alcohols by Pseudomonas cepacia lipase catalyzed transesterification in high enantiomeric ratio (E) under mild reaction conditions.
A chemoenzymatic methodology has been developed using indium-mediated allylation of heterocyclic aldehydes under aqueous conditions followed by Pseudomonas cepacia lipase-catalyzed enantioselective acylation of racemic homoallylic and homopropargylic alcohols in organic media. It is observed that the lipase immobilized on ceramic particles (PS-C Amano II) catalyzes the resolution in a highly enantioselective
Ceric(IV) Ammonium Nitrate: A Novel Reagent for the Synthesis of Homoallyl Alcohols
作者:J. S. Yadav、B. V. S. Reddy、A. D. Krishna、K. Sadasiv、Ch. Janardhana Chary
DOI:10.1246/cl.2003.248
日期:2003.3
allylation of aldehydes with allyltributylstannane using a catalytic amount of ceric ammonium nitrate in acetonitrile under mild and neutral conditions to afford the corresponding homoallyl alcohols in excellent yields with high chemoselectivity. Allylation of ketones has also been achieved with tetraallytin under similar reaction conditions.