Gold-Catalyzed Nitrene Transfer to Activated Alkynes: Formation of α,β-Unsaturated Amidines
摘要:
A gold-catalyzed intermolecular nitrene transfer to alkynes was developed for the first time, revealing a new mode of nitrene transfer and providing a novel access to versatile alpha-imino metal carbenes. Various mild nitrene-transfer reagents were examined, and iminopyridium ylides especially those based on 3,5-dichloropyridine proved be highly effective. With activated alkynes such as N-alkynyloxazolidinones as substrates, alpha,beta-unsaturated amidines were formed in mostly good yields.
Site-specific introduction of gold-carbenoids by intermolecular oxidation of ynamides or ynol ethers
作者:Paul W. Davies、Alex Cremonesi、Nicolas Martin
DOI:10.1039/c0cc02736g
日期:——
Ynamides and ynol ethers undergo intermolecular gold-catalysed reaction with a nucleophilic oxidant to access metal-carbenoid reactivity patterns. A site-specific oxidation/1,2-insertion cascade is used for a general access to functionalised α,β-unsaturated carboxylic acid derivatives and vinylogous carbimates.
Heterogeneously catalyzed selective aerobic oxidative cross-coupling of terminal alkynes and amides with simple copper(ii) hydroxide
作者:Xiongjie Jin、Kazuya Yamaguchi、Noritaka Mizuno
DOI:10.1039/c2cc31159c
日期:——
Simplecopper(II) hydroxide Cu(OH)(2) could act as an efficient heterogeneous catalyst for selectiveoxidative cross-coupling of a broad range of terminal alkynes and amides using air as a sole oxidant, giving the corresponding ynamides in moderate to high yields (56-93% yields).