Highly convenient one-pot conversion of aryl acylals or aryl aldehyde bisulfites into dihydropyrimidones using Bi(NO3)(3)center dot 5H(2)O

A new, facile, and efficient one-pot deprotection-cyclocondensation method is presented for the Biginelli reaction from aryl acylals or aryl aldehyde bisulfites in the presence of catalytic amounts of Bi(NO3)(3)center dot 5H(2)O under solvent-free conditions. In addition, high levels of chemoselectivity for this synthesis have been achieved. (c) 2007 Wiley Periodicals, Inc.