and dioxygen serve as oxidants in highly stereoselective oxidative Pd‐catalyzed Heck arylations in which aryl boronicacids are used to synthesize triarylalkyl‐substituted olefins. The reactions occur under very mild conditions at room temperature. As an example, the threefold sequential arylation of methyl acrylate is the crucial step in the stereoselective synthesis of Z‐Tamoxifen.
Silver sequestration of halides for the activation of Pd(OAc)
<sub>2</sub>
catalyzed Mizoroki‐Heck reaction of 1,1 and 1,2 ‐ Disubstituted alkenes
作者:Pronnoy G. Bangar、Priyanka R. Jawalkar、Swapnil R. Dumbre、Dharmaraj J. Patil、Suresh Iyer
DOI:10.1002/aoc.4159
日期:2018.3
A ligand free catalytic system consisting of Pd(OAc)2 (cat) and stoichiometric quantities of silver salts, AgOAc or AgBF4, exhibit high efficiency in the Mizoroki‐Heck arylation, transforming aryl iodides and 1,1 as well as 1,2disubstitutedalkenes into 1,1,2 – trisubstituted aryl alkenes in excellent yields in very short reaction times.
A rhodium-copper-TBAF-catalyzed hydroarylation of alkynes with aryl trimethoxysilanes is described. The procedure utilizes a catalytic amount of copper(II) acetate, rhodium, PPh3 and TBAF center dot 3H(2)O under air. Some asymmetric alkynes gave the products with high regioselectivities. (C) 2009 Elsevier Ltd. All rights reserved.
Dramatic Enhancement of Catalytic Activity in an Ionic Liquid: Highly Practical Friedel-Crafts Alkenylation of Arenes with Alkynes Catalyzed by Metal Triflates
作者:Choong Eui Song、Da-un Jung、Su Yhen Choung、Eun Joo Roh、Sang-gi Lee