Unusual allylic acetoxylations of silyl enol ethers with lead(IV) acetate
作者:Martine M.L. Crilley、David S. Larsen、Richard J. Stoodley、Fernando Tomé
DOI:10.1016/s0040-4039(00)73689-6
日期:1993.5
1-Siloxycyclohexenes, bearing an oxy group at position 3 and a syn-disposed cis-fused ring at positions 4 and 5, undergo regio- and stereo-selective acetoxylations (at position 6) in the presence of lead(IV) acetate.
Stereocontrolled synthesis of 4-demethoxy-7-O-methyldaunomycinone
作者:David A. Jackson、Richard J. Stoodley
DOI:10.1039/c39810000478
日期:——
The Diels–Alder adduct (6), prepared from 4a,9a-epoxy-4a,9a-dihydroanthracene-1,4,9,10-tetraone (3) and 1-methoxy-3-trimethylsilyloxybuta-1,3-diene, can be efficiently converted into the title compound (2b), a precursor of 4-demethoxydaunomycin (1d), by a five-step sequence.
The synthesis of 1-(3,4,5-trimethoxyphenyl)-3-trialkylsiloxy-1,3-butadienes and their Diels-Alder reaction with selected dienophiles at room temperature is described. These aryldienes are useful building blocks for the synthesis of natural and pharmacological active products, as has been shown by the preparation of a tetracyclic ketone needed for the synthesis of new anthracycline analogues. (C) 1997 Elsevier Science Ltd.