NHC-Mediated Stetter-Aldol and Imino-Stetter-Aldol Domino Cyclization to Naphthalen-1(2H)-ones and Isoquinolines

N-Heterocyclic carbene-catalyzed tandem Stetteraldol reaction of phthalaldehyde and alpha,beta-unsaturated ketimines has been developed to afford functionalized naphthalen-1(2H)-one derivatives as the formal [4+2] annulation product. Interestingly, the reaction of aldimines led to the formation of isoquinoline derivatives instead of the expected indanone derivatives as a [4+1] annulation product.

Automated summary

The N-heterocyclic carbene-catalyzed tandem Stetter-aldol reactions of phthalaldehyde and alpha,beta-unsaturated ketimines yielded functionalized naphthalen-1(2H)-one derivatives as [4+2] annulation products, while the reactions of aldimines resulted in the formation of isoquinoline derivatives instead of the expected indanone derivatives as [4+1] annulation products, showcasing a novel synthetic strategy.