Multifunctional odorless isocyano (triphenylphosphoranylidene)-acetates: synthesis and direct one-pot four-component Ugi/Wittig cyclization to multisubstituted oxazoles

The multifunctional odorless isocyano(triphenylphosphorany-lidene) acetate was prepared as a new stable phosphorus ylide containing isocyanide group. A new one-pot four component synthesis of multi-substituted oxazoles by a cascade Ugi/Wittig process without Mumm rearrangement has been developed, starting from the isocyano(triphenylphosphora-nylidene) acetates, aldehydes, amines and acids. Two component reactions of isocyano(triphenylphosphoranylidene)-acetates and acids also generated disubstituted oxazoles in good yields.