作者:Pascal Nösel、Laura Nunes dos Santos Comprido、Tobias Lauterbach、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1021/ja4085385
日期:2013.10.16
In the presence of a gold catalyst an unprecedented oxidativecyclization of diynes takes place. The reaction cascade is initiated by an oxygen transfer from a N-oxide onto a gold-activated alkyne. The formed α-oxo carbene is transferred across the second alkyne yielding a stabilized vinyl carbene/cation. Alkyl migration or sp(3)-CH insertion then terminates the catalytic cycle by formation of highly
Gold-catalyzed cyclization of propargylic diynes: Ethers vs acetates – Related products but different pathways
作者:Johannes Schädlich、Tobias Lauterbach、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1016/j.jorganchem.2015.04.053
日期:2015.10
Diyne substrates bearing one propargylic ether instead of the previously published propargylic acetates were subjected to a gold catalyst. alpha-Naphthol derivatives were obtained as products of the cycloisomerization. The close relationship of the products to the corresponding cyclizations implicated a related mechanistic scenary at first, but further studies favour a mechanistic pathway that is completely different. (C) 2015 Elsevier B.V. All rights reserved.