Erbium(III) triflate is a powerfulcatalyst for the acylation of alcohols and phenols. The reaction works well for a large variety of simple and functionalized substrates by using different kinds of acidicanhydrides Ac2O, (EtCO)2O, [(CH3)3CO]2O, Bz2O, and (CF3CO)2O} without isomerisation of chiral centres. Moreover, the catalyst can be easily recycled and reused without significant loss of activity
A wide variety of alcohols, phenols and amines are efficiently and selectively converted into the corresponding acetates by treatment with acetic anhydride in the presence of catalytic amounts of La(NO3)3·6H2O undersolvent-freeconditions at room temperature. The method is compatible with acid sensitive hydroxyl protecting groups such as TBDMS, THP, OBz, OBn, Boc and some isopropylidenes and offers
temperature of 200°C and CO pressure of 10-20 MPa. The reaction in the case of 1,3-propanediol gives γ-butyrolactone, with a selectivity of 60-% . Side reactions of homologation to 1,4-butanediol derivatives and hydrogenolysis to n-propyl derivatives by H2 produced by the water gas shift reaction (WGSR) also occur, together with acid-catalyzed dehydration to give linear polypropylene glycols, α,ω-diols
可以在200°C的温度下,在羰基碘化钌[Ru(CO)3 I 3 ] - /烷基或金属碘化物的存在下,将二醇及其甲酸或乙酸酯羰基化,以生成内酯或相应的醚羟基酸酯。C和CO压力为10-20 MPa。在1,3-丙二醇的情况下,反应产生选择性为60%的γ-丁内酯。还发生了由水煤气变换反应(WGSR)产生的H 2与Hg合成为1,4-丁二醇衍生物和氢解为正丙基衍生物的副反应,以及酸催化的脱水反应,生成线性聚丙二醇α,ω-链中具有3个以上碳原子的二醇优先提供羟基酸酯和醚。
Erbium(III) Chloride: a Very Active Acylation Catalyst
作者:Renato Dalpozzo、Antonio De Nino、Loredana Maiuolo、Manuela Oliverio、Antonio Procopio、Beatrice Russo、Amedeo Tocci
DOI:10.1071/ch06346
日期:——
Erbium(iii) chloride is a powerfulcatalyst for the acylation of alcohols and phenols. The reaction works well for a large variety of simple and functionalized substrates by using different kinds of acidicanhydrides (Ac2O, (EtCO)2O, (PriCO)2O, (ButCO)2O, and (CF3CO)2), without isomerization of chiral centres. Moreover, the catalyst can be easily recycled and reused without significant loss of activity
A Cheap, Simple, and Versatile Method for Acetylation of Alcohols and Phenols and Selective Deprotection of Aromatic Acetates Under Solvent‐Free Condition
作者:Fatemeh Rajabi、Mohammad R. Saidi
DOI:10.1081/scc-200048988
日期:2005.1.1
Abstract Acyclic and cyclic acetates of various alcohols and phenols were obtained in excellent yields under mild reaction conditions in the presence of a catalytic amount of sodium hydroxide under solvent–free conditions and microwave irradiation. Selective deprotection of acetate group from the corresponding phenolic compounds was carried out in the presence of LiClO4.2H2O.