Hexafluoroisopropyl alcohol mediated synthesis of 2,3-dihydro-4H-pyrido[1,2-a]pyrimidin-4-ones.

An efficient synthesis of novel 2,3-dihydro-4H-pyrido[1,2-a]pyrimidin-4-ones has been reported. Inexpensive and readily available substrates, environmentally benign reaction condition, and product formation up to quantitative yield are the key features of this methodology. Products are formed by the aza-Michael addition followed by intramolecular acyl substitution in a domino process. The polar nature and strong hydrogen bond donor capability of 1,1,1,3,3,3-hexafluoropropan-2-ol is pivotal in this cascade protocol.