An efficient and highly regioselective synthesis of fully substituted furans has been described using Ca(OTf)2. The reaction proceeds through tandem alkylation, 5-exo dig cyclisation and isomerization under solvent free conditions.

An amine-triggered facile synthetic approach of anthranilates has been described through benzannulation of readily available chemicals under one-pot solvent-free conditions using Ca(OTf) 2 as the sustainable catalyst. In this regioselective approach, we described a reasonably longer cascade, which proceeds through β-enamino ester formation/Michael addition/intramolecular aldol reaction/elimination/aromatization/oxidative debenzylation/lactonization with a broad substrate scope and high yields. The isolation of intermediates authenticated the mechanism, and the synthetic utility of the products was also demonstrated.

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