Palladium-Catalyzed Cascade Cyclization–Oxidative Olefination of tert-Butyl 2-Alkynylbenozates
摘要:
Palladium(II) can catalyze the oxidative coupling of tert-butyl 2-alkynylbenzoates with olefins such as acrylates and styrenes, leading to isocoumarines. The reaction was carried out under simple aerobic conditions, and in most cases, high selectivity has been attained.
Highly regioselective nucleopalladation for the oxidative coupling of internal alkynes with alkenyl alcohols by using green and low-costing oxygen as the sole oxidant was investigated. This one-pot cascade cyclization proceeds through Pd-catalyzed intramolecular C–O bond cyclization, insertion of nonbiased alkenyl alcohols, β-H elimination, and reinsertion of a HPdX species, which is finally transferred