Gold- and Silver-Catalyzed Reactions of Propargylic Alcohols in the Presence of Protic Additives
作者:Matthew N. Pennell、Peter G. Turner、Tom D. Sheppard
DOI:10.1002/chem.201102830
日期:2012.4.10
secondary and tertiary propargylicalcohols undergo a Meyer–Schusterrearrangement to give enones at room temperature in the presence of a gold(I) catalyst and small quantities of MeOH or 4‐methoxyphenylboronic acid. The syntheses of the enone natural products isoegomaketone and daphenone were achieved using this reaction as the key step. The rearrangement of primary propargylicalcohols can readily be combined
Three different substituted thiazoles have been successfully synthesized from readily available propargylic alcohols. Various secondary propargylic alcohols or tertiary propargylic alcohols participated well in the reaction, providing the desired products in good yields. This method provides a flexible and rapid route to substituted thiazoles.
Gold-Catalyzed Efficient Formation ofα,β-Unsaturated Ketones from Propargylic Acetates
作者:Meng Yu、Guotao Li、Shaozhong Wang、Liming Zhang
DOI:10.1002/adsc.200600579
日期:2007.4.2
An efficient gold-catalyzed method for the preparation of α,β-unsaturated ketones from propargylic acetates has been developed. Under mild reaction conditions, β-monosubstituted enones were formed mostly with excellent E-selectivity. β,β-Disubstituted enones can be prepared from propargylic acetates derived from ketones. The high efficiency and mild nature of this reaction render it a viable alternative
Tetrabutylammonium Fluoride (TBAF)-Catalyzed Addition of Substituted Trialkylsilylalkynes to Aldehydes, Ketones, and Trifluoromethyl Ketones
作者:Venkat Reddy Chintareddy、Kuldeep Wadhwa、John G. Verkade
DOI:10.1021/jo200314g
日期:2011.6.3
efficient catalyst for the addition of trialkylsilylalkynes to aldehydes, ketones, and trifluoromethyl ketones in THF solvent at room temperature. The reaction conditions are mild and operationally simple, and a variety of aryl functional groups, such as chloro, trifluoromethyl, bromo, and fluoro groups, are tolerated. Impressively, using our protocol, useful CF3-bearing tertiary propargylic alcohols
Chemo- and Regioselective Assembly of Polysubstituted Pyridines and Isoquinolines from Isocyanides, Arynes, and Terminal Alkynes
作者:Feng Sha、Luling Wu、Xian Huang
DOI:10.1021/jo300072x
日期:2012.4.20
strategy for polysubstitutedpyridines and isoquinolines with high chemo- and regioselectivity. In this methodology, 1-alkynyl imines act as the key compound to undergo a sequential alkynyl imine–allenyl imine isomerization/aza-Diels–Alder reaction/aromatization. In the first place, 1-alkynyl imines were formed in situ by a highly selective multicomponentreaction of isocyanides, arynes, and terminal alkynes