Synthesis of densely functionalized 3a,4-dihydro-1H-pyrrolo[1,2-b]pyrazoles via base mediated domino reaction of vinyl malononitriles with 1,2-diaza-1,3-dienes.

A domino reaction of vinyl malononitriles (VMs) with 1,2-diaza-1,3-dienes (DDs) produce unprecedented 3a,4-dihydro-1H-pyrrolo[1,2-b]pyrazole systems in a chemo-, regio-, and stereoselective fashion. This base promoted (DIPEA) one-pot transformation involving multiple steps constructs one new C-C bond, two C-N bonds, and two new fused heterocyclic rings with total atom economy.