Copper-Catalyzed Regio- and Stereoselective Intermolecular Three-Component Oxyarylation of Allenes
摘要:
A copper(II)-catalyzed intermolecular three-component oxyarylation of allenes using arylboronic acids as a carbon source and TEMPO as an oxygen source is described. The reaction proceeded under mild conditions with high regio- and stereo-selectivity and functional group tolerance. A plausible reaction mechanism is proposed, involving carbocupration of allenes, homolysis of the intervening allylcopper(II), and a radical TEMPO trap.
Palladium-Catalyzed Regioselective Coupling of Propargylic Substrates with Terminal Alkynes. Application to the Synthesis of 1,2-Dien-4-ynes
摘要:
The palladium-catalyzed reaction of propargyl halides, tosylates and acetates with terminal alkynes is reported. The best yields are obtained from propargyl chlorides and 1-alkynes (i) in the presence of 2 equiv. of amine (triethylamine, diisopropylamine) in benzene, toluene or ethylacetate (ii) or in pure diisopropylamine. Propargyl acetates undergo the cross coupling reaction with moderate to high yields after modification of the general procedure. (C) 2000 Elsevier Science Ltd. All rights reserved.
An efficient palladium-catalysed reaction of propargyl halides tosylates and acetates with terminal alkynes
作者:Sylvie Gueugnot、Gérard Linstrumelle
DOI:10.1016/s0040-4039(00)79245-8
日期:1993.6
In the presence of palladium complexes and copper iodide, the reaction of propargyl halides with terminal alkynes proceeds rapidly to give conjugated allenynes in high yield. Propargyl acetates and tosylates are also suited to the preparation of such allenes.