Iridium-catalyzed crossed aldol coupling and a new concept to form an Ir–Si species
摘要:
[Ir(COD)(PPh3)(2)]X (X=PF6, ClO4, and OTf) activated by H-2 molecule catalyzes Mukaiyama-type aldol coupling between enoxysilanes and acetals or aldehydes. An Ir-Si species formed in the first stage of the catalytic cycle plays an important role in these reactions. (C) 2000 Elsevier Science Ltd. All rights reserved.
The biocatalytic Friedel-Crafts acylation has been identified recently for the acetylation of resorcinol using activated aceticacidesters for the synthesis of acetophenone derivatives catalyzed by an acyltransferase. Because the wild-type enzyme is limited to acetic and propionic derivatives as the substrate, variants were designed to extend the substrate scope of this enzyme. By rational protein
Breederveld; Kooyman, Recueil des Travaux Chimiques des Pays-Bas, 1957, vol. 76, p. 297,310
作者:Breederveld、Kooyman
DOI:——
日期:——
Hydroxy-Directed Amidation of Carboxylic Acid Esters Using a Tantalum Alkoxide Catalyst
作者:Hiroaki Tsuji、Hisashi Yamamoto
DOI:10.1021/jacs.6b09482
日期:2016.11.2
the chemoselective synthesis of amides by using a metal-catalyzed hydroxy-directed reaction. A hydroxy group located at the β-position of an ester group promoted the activation of a carbonyl group with a tantalum alkoxide catalyst followed by amidation reactions, leading to a wide variety of β-hydroxyamides with excellent chemeselectivity. The chemoselective amidation strategy can be extended to the
[Ir(COD)(PPh3)(2)]X (X=PF6, ClO4, and OTf) activated by H-2 molecule catalyzes Mukaiyama-type aldol coupling between enoxysilanes and acetals or aldehydes. An Ir-Si species formed in the first stage of the catalytic cycle plays an important role in these reactions. (C) 2000 Elsevier Science Ltd. All rights reserved.