Electrogenerated Acid-Catalyzed Reactions of Acetals, Aldehydes, and Ketones with Organosilicon Compounds, Leading to Aldol Reactions, Allylations, Cyanations, and Hydride Additions
electrogenerated acid (EG acid) in the silicon-mediated acid-catalyzed reactions; e.g., aldol reactions, allylations, cyanations, and hydride additions is described. The aldol reaction of acetals 1 with enol trimethylsilyl ethers 3 and 1,2-bis(trimethylsiloxy)alkenes 4 gives the corresponding adducts 5 and 6, respectively. The reaction proceeds smoothly with EG acid derived from perchlorate salts such
Sc<sup>III</sup>-Doped Zeolites as New Heterogeneous Catalysts: Mukaiyama Aldol Reaction
作者:Andrea Olmos、Aurélien Alix、Jean Sommer、Patrick Pale
DOI:10.1002/chem.200901647
日期:2009.10.26
ScIII‐doped solids based on zeolite materials have been investigated for the first time as catalysts in organic synthesis. ScIII–USY zeolite proved to be a novel and very efficient heterogeneouscatalyst for the Mukaiyama aldol reaction. This easy‐to‐prepare catalyst exhibited wide scope and compatibility with functional groups and is very simple to use, easy to remove (by simple filtration), and is
首次研究了以沸石材料为基础的掺有Sc III的固体作为有机合成中的催化剂。Sc III –USY沸石被证明是Mukaiyama羟醛反应的一种新型且非常有效的非均相催化剂。这种易于制备的催化剂具有广泛的用途和与官能团的相容性,使用非常简单,易于去除(通过简单过滤),并且可循环使用(最多可重复使用三遍,而不会损失活性)。
An Efficient and Extremely Mild Catalyst System, Combined Use of Trityl Chloride and Tin(II) Chloride, in the Aldol and Michael Reactions
The aldol reaction of silyl enol ethers with acetals or aldehydes, and the Michael reaction of silyl enol ethers with α,β-unsaturated ketones are efficiently catalyzed by the combined use of trityl chloride and tin(II) chloride under extremely mild conditions.
甲硅烷基烯醇醚与缩醛或醛的羟醛反应,以及甲硅烷基烯醇醚与 α,β-不饱和酮的迈克尔反应通过三苯甲基氯和氯化锡 (II) 的联合使用在极其温和的条件下有效催化。
Crossed aldol-type reactions catalyzed by rhodium complexes
作者:Susumu Sato、Isamu Matsuda、Yusuke Izumi
DOI:10.1016/0022-328x(88)83037-7
日期:1988.9
ketones. Rh4(CO)12 and [Rh(COD)(DPPB)]ClO4 also catalyze the reaction of enol trimethylsilyl with acetals or ketals, whereas [Rh(COD)(DPPB)PF6 does not. When [Rh(COD)(DPPB)ClO4 is used as the catalyst, this type of aldol reaction is extended to the one-potsynthesis of trisubstituted furans from enol trimethylsilyl ether and α-trimethylsiloxy acetal.
A cationic iridium complex [Ir(cod)2]SbF6 was found to be a new and efficient Lewis acid catalyst for Mukaiyama aldol and Mannich reactions. Aldehydes react smoothly with silyl enol ethers to give β-siloxy ketones in the presence of 0.5 mol % of [Ir(cod)2]SbF6. The reaction of N-alkyl arylaldimines with ketene silyl acetals in the presence of 5 mol % [Ir(cod)2]SbF6/P(OPh)3 gave β-amino esters. After