A polymer-assisted solution-phase strategy for the synthesis of fused [2,1-b]quinazolinones and the preparation of optically active vasicinone

An efficient preparation of fused [2,1-b]quinazolinones has been developed utilizing polymer-supported reagents. (+/-)Vasicitione was converted into its dione by oxidation with poly (4-vinylpyridiniumdichromate). An efficient method has been developed for the synthesis of (d)- and (l)-vasicinone via asymmetric reduction of pyrrolo[2,1-b]quinazoline-3,9-dione by employing NaBH4/Me3SiCl as the reducing agent and polymer-supported chiral sulfonamide as catalyst.