Palladium(II) acetate in association with secondary phosphine oxides provides an efficient catalytic system for [2+1] cycloadditions starting from oxanorbornene derivatives and tertiary propargyl esters giving rise to vinylidenecyclopropanes. This reaction is specific to bidentate phosphinito–phosphinous acid ligands generated from secondary phosphine oxides. The [2+1] cycloaddition was found broad
Convenient Synthesis of meso-Cyclohexa-1,3-dienes by One-Pot Two-Step Deoxygenation of 7-Oxabicyclo[2.2.1]hept-2-enes
作者:Ryo Irie、Tomotsugu Yano、Takashi Fujishima
DOI:10.1055/s-0029-1218618
日期:2010.3
Iron(III) hydroxide oxide was found to be an efficient catalyst for the ring-opening reaction of 5,6-cis-disubstituted 7-oxabicyclo[2.2.1]hept-2-enes with acetyl bromide in dichloromethane at room temperature to give cyclohexene derivatives with leaving groups (acetoxy or bromo groups) disposed on each allylic position. A successive one-pot treatment of the reaction mixture with zinc powder and tetrahydrofuran
Gilchrist, Thomas L.; Wood, Jane E., Journal of the Chemical Society. Perkin transactions I, 1992, # 1, p. 9 - 16
作者:Gilchrist, Thomas L.、Wood, Jane E.
DOI:——
日期:——
Enantioselective synthesis of the medium ring ethers, tetrahydrooxepin, oxocane and hexahydrooxonin, of ciguatoxin. Extensive ring-expansion and chemoenzymatic desymmetrization strategy
The extensive ring-expansion strategy for the synthesis of tetrahydrooxepin, oxocane, and hexahydrooxonin, which correspond to the D(E), I and F rings of ciguatoxin (CTX1B, 1), respectively, has been established. Chemoenzymatic acylation of the meso alcohols using a lipase provides an expeditious entry for the enantiomeric building blocks. (C) 1999 Elsevier Science Ltd. All rights reserved.