Aniline-terephthalaldehyde resin <i>p</i>-toluenesulfonate (ATRT) as a highly efficient and reusable catalyst for alcoholysis, hydrolysis, and acetolysis of epoxides
作者:Kiyoshi Tanemura、Tsuneo Suzuki
DOI:10.1080/00397911.2016.1223309
日期:2016.11.16
ABSTRACT Alcoholysis, hydrolysis, and acetolysis of epoxides were carried out in the presence of a catalytic amount of aniline-terephthalaldehyde resin p-toluenesulfonate (ATRT) to give the corresponding β-substituted alcohols in good yields. Alcoholysis and hydrolysis of epoxides catalyzed by ATRT proceeded faster than those by pyridinium p-toluenesulfonate (PPTS). GRAPHICAL ABSTRACT
Carbon Tetrabromide: An Efficient Catalyst for Regioselective Ring Opening of Epoxides with Alcohols and Water
作者:J. S. Yadav、B. V. Reddy、K. Harikishan、Ch. Madan、A. V. Narsaiah
DOI:10.1055/s-2005-918422
日期:——
Epoxides undergo rapid ringopening with a range of alcohols in the presence of catalytic amount of carbon tetrabromide under mild and convenient conditions to afford the corresponding β-alkoxy alcohols and 1.2-diols in high yields with high regioselectivity.
Ytterbium Trifluoromethanesulfonate Yb(OTf)3: An Efficient, Reusable Catalyst for Highly Selective Formation of β-Alkoxy Alcohols via Ring-Opening of 1,2-Epoxides with Alcohols
作者:Pravin R. Likhar、Manyam Praveen Kumar、Ananda K. Bandyopadhyay
DOI:10.1055/s-2001-14909
日期:——
Ytterbium(III)triflate-catalysed ring-opening reactions of epoxides derived from styrene, cyclohexene, norbornene and stilbene, in the presence of alcohols (C1-C4 1°, 2° and 3° aliphatic alcohols, cyclohexyl alcohol, allyl and propargyl alcohol) resulted in the formation of β-alkoxy alcohols in good to excellent yield with high regio-, and where applicable, stereoselectivity. Reaction of stilbene oxide with methanol in the presence of the diethyl ester of l-(+)-tartaric acid afforded the threo form of 1,2-diphenyl-2-methoxy ethanol with high diastereoselectivity (de 94%). Mechanistic implications of the results are discussed.
A highly effective protocol for ring opening of epoxides with allyl and propargyl alcohols, aniline and thiophenol in the presence of catalytic amounts of B(C6F5)(3) has been developed. Benzyl, tetrahydropyranyl, tert-butyldimethyl silyl protecting groups were stable under the reaction conditions. (C) 2002 Elsevier Science Ltd. All rights reserved.