Reaction of Allylsilanes and Allylstannanes with Alkynes Catalyzed by Electrophilic Late Transition Metal Chlorides
作者:Carolina Fernández-Rivas、María Méndez、Cristina Nieto-Oberhuber、Antonio M. Echavarren
DOI:10.1021/jo025812n
日期:2002.7.1
The intramolecular reaction of allylsilanes and allylstannanes with alkynes proceeds catalytically in the presence of Pt(II), Pd(II), Ru(II), and Au(III) chlorides. Although more limited, AgOTf also catalyzes the cyclization. Usually, PtCl2 as the catalyst in methanol or acetone gives the best results. The reaction proceeds by exo attack of the allyl nucleophile on the alkyne to form five- or six-membered
Allyl stannanes as electrophiles or nucleophiles in the palladium-catalyzed reactions with alkynes
作者:Belén Martı́n-Matute、Elena Buñuel、Marı́a Méndez、Cristina Nieto-Oberhuber、Diego J Cárdenas、Antonio M Echavarren
DOI:10.1016/j.jorganchem.2003.07.027
日期:2003.12
The reactivity of the allylstannanes can be inverted by changing the oxidation state of the catalyst from Pd(II) to Pd(0). Whereas with Pd(II) an anti nucleophilic attack of the allylstannane on the alkyne takes place, the reaction with Pd(0) proceeds by oxidative addition to form (η3-allyl)palladium complexes leading to a formal syn addition to the alkyne. This mechanistic proposal is supported