The Total Synthesis of (−)-7-Deoxyloganin via <i>N</i>-Heterocyclic Carbene Catalyzed Rearrangement of α,β-Unsaturated Enol Esters
作者:Lisa Candish、David W. Lupton
DOI:10.1021/ol101983h
日期:2010.11.5
The diastereoselective N-heterocyclic carbene (NHC) catalyzed rearrangement of α,β-unsaturated enolester (S)-2b has been used to assemble dihydropyranone (S)-3b, a material embodying the bicyclic core of the iridoid family of natural products. Elaboration of this intermediate, by chemoselective reduction followed by stereoselective β-glycosylation, has allowed the total synthesis of (−)-7-deoxyloganin
Substitution nucleophile d'acetates de cyclenols allyliques fonctionnels par des organometalliques en presence de sels cuivreux. Application a une synthese rapide de la (±)mitsugashiw alactone
作者:Hassen Amri、Monique Rambaud、Jean Villieras
DOI:10.1016/s0040-4020(01)81522-2
日期:1990.1
Substitution of functional allylic cycloalkenol acetates by Grignardreagents (primary , secondary, tertiary-alkyl, vinyl, aryl) in the presence of a catalytic amount (2.5% equivalent) of cuprous iodide at low temperature, gives high yields of various functional α-substituted cycloalkenes . The reaction can be applied to lithium enolates of esters and need no catalyst, but may be performed with HMPA