Substrate-Controlled Three-Component Synthesis of Diverse Fused Heterocycles

A chemoselective strategy toward a variety of fused heterocyclic
scaffolds relying on a three-component condensation of heterocyclic
ketene aminals (HKAs) or corresponding thioaminals with aryl glyoxals
and cyclic 1,3-dicarbonyl compounds has been developed and explored.
Depending on the applied combination of substrates, the strategy can
be tuned to provide straightforward access to imidazo[1,2-a]quinoline, pyrrolo[1,2-a]imidazole, and
pyrrolo[2,1-b]thiazole frameworks.