摘要
This work reports the construction of cyclopentene cores from 1,6-enynes and aryl diazo ketones through two new reaction sequences involving initial gold-catalyzed cyclization of 1,6-enynes with diazo species, followed by rhodium-catalyzed skeletal rearrangement of the resulting 3-cyclopropyl-2-en-1-ones. In most instances the rhodium-catalyzed reactions afforded cyclopentene derivatives whereas several n-alkyl- or ortho-substituted phenyl ketones delivered seven-membered oxacycles. A plausible mechanism provides rationales for these two distinct products. (Figure presented.).