Trifluoromethanesulfonic acid (HOTf) promoted cross-coupling of ortho-[2-(4-methoxylphenyl)-alkynyl]acetophenones with ortho-alkynylbenzaldehydes affording chrysene derivatives has been developed. The present cascade reaction provides a facile one-pot synthesis of multisubstituted chrysenes as well as naked chrysene under mild conditions. The mechanism experimental results demonstrate isochromenylium is a key intermediate for this transformation.

An efficient, one-pot synthesis of multisubstituted 2-aminoquinolines from 1-aryl tetrazoles and internal alkynes has been developed. The reaction involves cyclization of 1-aryl tetrazoles with internal alkynes via rhodium(III)-catalyzed double C-H activation and copper(II)-mediated denitrogenation.

A novel and efficient protocol for the synthesis of benzofulvene derivatives from easily available diarylacetylenes has been developed. The reaction proceeds through rarely reported carboxylate-assisted alkyne-directed ortho-C(sp(2))-H palladation followed by insertion of another diarylacetylene.

An efficient route for highly substituted chrysene derivatives via operationally simple copper-catalyzed one-pot dimerization of 2-alkynyl-1-acetylbenzenes is described.

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