The vinylogous anomeric effect in 3-alkyl-2-chlorocyclohexanone oximes and oxime ethers
作者:Scott E. Denmark、Michael S. Dappen、Nancy L. Sear、Robert T. Jacobs
DOI:10.1021/ja00165a034
日期:1990.4
(methyl, ethyl, isopropyl, and tert-butyl), have been prepared and shown to exist predominantly in the diequatorial chair conformation except the tert-butyl derivative which prefers a twist-boat. Formation of the oximes and various oxime derivatives (methyloxime, silyloxime) results in a remarkable conformational inversion for the methyl, ethyl, and isopropyl systems. By analysis of vicinal interproton
Equatorial Preference in the GaCl<sub>3</sub>-Promoted Ethenylation of Cyclic Ketones
作者:Masahiko Yamaguchi、Mieko Arisawa、Chie Miyagawa
DOI:10.1055/s-2002-19298
日期:——
Silylenolethers derived from substituted cyclohexanones are ethenylated with trimethylsilylethyne in the presence of GaCl 3 . Carbon-carbonbondformation was completed in less than 5 min at room temperature and protodegallation of the organogallium intermediate formed with 6 M sulfuric acid gave β-enones. The reactions exhibit a bias for the equatorial C-C bondformation, which contrasts the axial
由取代的环己酮衍生的甲硅烷基烯醇醚在 GaCl 3 存在下用三甲基甲硅烷基乙炔乙烯化。在室温下,碳-碳键的形成在不到 5 分钟的时间内完成,用 6 M 硫酸形成的有机镓中间体的原脱镓过程得到 β-烯酮。该反应表现出对赤道CC键形成的偏差,这与烯醇烷基化的轴向立体化学形成对比。讨论了这种立体选择性的起源。
DENMARK, SCOTT E.;DAPPEN, MICHAEL S.;SEAR, NANCY L.;JACOBS, ROBERT T., J. AMER. CHEM. SOC., 112,(1990) N, C. 3466-3474
作者:DENMARK, SCOTT E.、DAPPEN, MICHAEL S.、SEAR, NANCY L.、JACOBS, ROBERT T.
DOI:——
日期:——
Palladium-Catalyzed Saegusa–Ito Oxidation: Synthesis of α,β-Unsaturated Carbonyl Compounds from Trimethylsilyl Enol Ethers
作者:Yingdong Lu、Pierre Long Nguyen、Nicolas Lévaray、Hélène Lebel
DOI:10.1021/jo302465v
日期:2013.1.18
Palladium-catalyzed Saegusa–Ito oxidation of trimethylsilylenolethers is possible using Oxone as a stoichiometric oxidant and sodium hydrogen phosphate as a buffer. Cyclic and acyclic enones as well as α,β-unsaturated aldehydes are obtained in good to excellent yields.