Oxidative Cyclization of β-Aminoacrylamides Mediated by PhIO: Chemoselective Synthesis of Isoxazoles and 2H-Azirines
摘要:
Cyclization of a variety of beta-aminoacrylamides in the presence of iodosobenzene (PhIO) is described. This process features mild reaction conditions, simple execution, and high chemoselectivity and thereby provides an efficient protocol for the divergent synthesis of substituted isoxazoles and 2H-azirines via switchable N-O and N-C bond formation controlled by simply varying the beta-substituent R-3 of the readily available substrates.
Vilsmeier Reaction of 3-Aminopropenamides: One-Pot Synthesis of Pyrimidin-4(3H)-ones
摘要:
A facile one-pot synthesis of pyrimidin-4(3H)-ones was developed via reactions of a series of readily available 3-aminopropenamides with varied Vilsmeier reagents, and a mechanism involving sequential halogenation, formylation, and intramolecular nucleophilic cyclization is proposed.