作者:Andrew L. Kocen、Maurice Brookhart、Olafs Daugulis
DOI:10.1039/c7cc04953f
日期:——
We report a method for palladium-catalysed chain-running isomerization of terminal and internal alkenes. Using an air-stable 2,9-dimethylphenanthroline-palladium catalyst in combination with NaBAr4 promoter, olefins are converted to the most stable double bond isomer at −30 to 20 °C. Silyl enol ethers are readily formed from silylated allylic alcohols. Fluorinated substituents are compatible with the
Unprecedented alkylation of silicon enolates with alcohols via carbenium ion formations catalyzed by tin hydroxide-embedded montmorillonite
作者:Michael Andreas Tandiary、Masashi Asano、Taiki Hattori、Satoshi Takehira、Yoichi Masui、Makoto Onaka
DOI:10.1016/j.tetlet.2017.03.073
日期:2017.5
The solid acid, tin hydroxide-embedded montmorillonite, catalyzes the unprecedentedalkylation of various silicon enolates with primary, secondary and tertiary benzylic alcohols as well as secondary allylic alcohols. The acid catalysis of Sn-Mont was not only higher than that of the other ion-exchanged montmorillonites (M-Mont; M = H, Ti, Fe and Al), but also higher than that of the typical homogeneous
固体酸,氢氧化锡包埋的蒙脱石可催化各种烯醇硅与伯,仲和叔苄醇以及仲烯丙基醇的空前烷基化。Sn-Mont的酸催化作用不仅高于其他离子交换的蒙脱土(M-Mont; M = H,Ti,Fe和Al),而且高于典型的均相酸催化剂(如BF)3 ·OEt 2,TMSOTf和TfOH。
AN EFFICIENT METHOD FOR THE PREPARATION OF<i>THREO</i>CROSS-ALDOLS FROM SILYL ENOL ETHERS AND ALDEHYDES USING TRITYL PERCHLORATE AS A CATALYST
Threo cross-aldol products are predominantly formed in good yields by treating tert-butyldimethylsilyl enol ethers with aldehydes in the presence of a catalytic amount of tritylperchlorate.
Use of organoaluminum reagents induces ene-like reactions of enol silyl ethers with aldehydes, and enols having bulky silyl groups selectively afforded syn adducts.
Preparation of -butyldimethylsilyl (tbdms) enol ethers using potassium hydride in the presence of tbdms chloride
作者:John Orban、John V. Turner、Bruce Twitchin
DOI:10.1016/s0040-4039(01)91129-3
日期:1984.1
TBDMS enolethers can be readily prepared regio- and stereoselectively under equilibrating conditions in high yield by adding potassiumhydride to a THF solution of ketone with TBDMS chloride in situ.