heterocyclic compounds from hydroxylated enynes has been developed. In this reaction, hydroxylated enynes were selectively transformed into five‐membered heterocyclic compounds 2, with an allene moiety at the 3‐position, in the presence of F3CSO3H (0.1 mol %). When R1, R2=Ph, diphenylvinyl‐2,3‐dihydro‐1H‐pyrrole (2 y) was obtained. With HSbF6 (5 mol %) as the catalyst, polycyclic skeletons 3 and 4 with adjacent
A mild and direct process for C−C bond formation from propargylic alcohols and olefin has been developed in the presence of a silver catalyst. In this reaction, trace amounts of water were necessary and allene alcohols 2 and 1,3-dienes 3 were obtained selectively.
A method for preparing five- or six-membered heterocyclic compounds from enyne carbonates via palladium catalysis was developed. Enyne carbonates were transformed into 3-vinylidene-1-tosylpyridines 2 in the presence of PdI2 as the catalyst. Using Pd(dba)(2) as the catalyst, 3-vinylidene-1-tosylpyrrolidines 3 were obtained. Further functionalizations of compounds 3 were carried out in a one-pot manner.