Intramolecular Nucleophilic Acyl Substitution Reaction of 3,4-Alkadienyl Carbonates Mediated by Ti(O-<i>i</i>-Pr)<sub>4</sub>/2 <i>i</i>-PrMgCl Reagent. Efficient Synthesis of Optically Active β,γ-Unsaturated Esters with an α-Substituent
作者:Yukio Yoshida、Sentaro Okamoto、Fumie Sato
DOI:10.1021/jo961401t
日期:1996.1.1
readily generated by the reaction of Ti(O-i-Pr)(4) with 2 i-PrMgCl, resulted in an intramolecular nucleophilic acyl substitution (INAS) reaction to afford vinyltitanium compounds 3 which, in turn, reacted with H(3)O(+), D(2)O, or iodine to give alpha-substituted beta,gamma-unsaturated esters 4 in good to excellent yields. The olefin moiety of the hydrolysis product 4 has (Z)-geometry mainly except for