Gold-Catalyzed Allyl-Allyl Coupling

摘要

The palladium(0)-catalyzed cyclization of allylstanhanes with allyl acetates in substrates of type 1 gives the five- or six-membered rings 2. This cross-coupling reaction proceeds by oxidative addition of the allyl acetate to Pd~0 followed by transmetalation and an allyl/allyl reductive elimination. After a search for other metal complexes that might promote the cyclization of substrates 1 to give 2 more efficiently and with better stereoselectivity, we found that cationic Au~I complexes outperform all other catalysts for this process (Scheme 1).