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.
Stereoselective Synthesis of 4-Substituted Cyclic Sulfamidate-5-Phosphonates by Using Rh-Catalyzed, Asymmetric Transfer Hydrogenation with Accompanying Dynamic Kinetic Resolution
作者:Yeon Ji Seo、Jin-ah Kim、Hyeon-Kyu Lee
DOI:10.1021/acs.joc.5b01434
日期:2015.9.4
asymmetric transfer hydrogenation of 4-substituted cyclic sulfamidate imine-5-phosphonates produces the corresponding cyclic sulfamidate-5-phosphonates. The process employs a HCO2H/Et3N mixture as the hydrogen source and the chiral Rh catalysts, (R,R)- or (S,S)-Cp*RhCl(TsDPEN), and it takes place at room temperature within 1 h with high yields and high levels of stereoselectivity.
由动态动力学拆分驱动的4-取代的环状氨基磺酸亚胺-5-膦酸酯的不对称转移氢化反应生成了相应的环状氨基磺酸5-膦酸酯。该方法使用HCO 2 H / Et 3 N混合物作为氢源和手性Rh催化剂((R,R)-或(S,S)-Cp * RhCl(TsDPEN) 1 h具有高收率和高水平的立体选择性。