l-Proline-Catalysed One-Pot Regio- and Diastereoselective Synthesis of Spiro[pyrido[2,3-d]pyrimidin-2-amine-6,5′-pyrimidines] in Water
Received: 29 March 2017
Accepted after revision: 21 May 2017
29 June 2017 (online)
A simple l-proline-catalysed regio- and diastereoselective synthesis of spiro[pyrido[2,3-d]pyrimidin-2-amine-6,5′-pyrimidines] in water through a strategy of one-pot multicomponent domino reaction of 2,6-diaminopyrimidin-4-one, aldehydes and barbituric acids is described. The notable advantages of the protocol are operational simplicity, mild reaction conditions, simple purification process involving no chromatographic techniques, wide substrate scope, and high yields. The method delivers the desired product within short reaction time and with a diastereoselectivity of 61:39 to 100:0, which makes the protocol highly attractive.