Pure Appl. Chem., 2006, Vol. 78, No. 2, pp. 397-407
http://dx.doi.org/10.1351/pac200678020397
Alkoxy- and hydroxycyclization of enynes catalyzed by Pd(II) and Pt(II) catalysts
Abstract:
The development of a novel reaction ideal in terms of atom economy was achieved. The scope of the reaction was evaluated in the presence of Pd and Pt catalysts. The first enantioselective Pt-promoted enyne carboalkoxycyclization was developed in up to 85 % stereoselectivity. This ideal atom-economical reaction afforded the corresponding functionalized five-membered carbo- and heterocycles in good to excellent yields. The use of silver salts combined with (R)-Ph-BINEPINE, a monophosphane atropisomeric ligand, was found to be the best-suited combination for moderate to high enantioselectivities on carbonated and nitrogenated substrates.