Synthesis of functionalized phenolic derivatives via the benzannulation of dienylketenes formed by a thermal wolff rearrangement of α-diazo-β-keto compounds
Eleven conjugated dienyl α-diazo-β-keto derivatives were prepared from α,β-unsaturated carbonyl compounds. Their thermolysis induced a Wolff rearrangement generating an intermediate dienyl ketene whose isomer which has the required configuration of the internal double bond underwent a benzannulation thus forming the corresponding phenolic derivatives. When γ-substituted by a methoxy group both stereoisomers
Trimethylsilylated 1,3-dienes or styrenes from the reaction between trimethylsilyldiazomethane and vinyl or aryl ketenes
作者:Françoise Léost、Alain Doutheau
DOI:10.1016/s0040-4039(98)02536-2
日期:1999.1
The reaction between trimethylsilyldiazomethane and aryl or vinyl ketenes 2 and 7, bearing an electron withdrawing group on the ketene moiety, gave rise in moderate to good yields to the trimethylsilylated styrenes 3–5 or 1,3 dienes 8a-d resulting from the decarbonylation of presumed intermediate cyclopropanones.
Vinylketene-enamine cyclocondensation: a new access to functionalized phenols
作者:Didier Collomb、Alain Doutheau
DOI:10.1016/s0040-4039(97)00034-8
日期:1997.2
The cyclocondensation between vinylketenes 2, generated by rhodium acetate catalysed Wolff rearrangement of diazo compounds 1, and enamines 3 led to functionalized phenolic derivatives 5 in moderate to good yields. (C) 1997 Published by Elsevier Science Ltd.