Copper (II) Triflate/ Vitamin-C Promoted Modified Morita-Baylis-Hillman Annulation: A Facile Route to Fluorescent Cyclopentene Derivatives.

Herein we report a rapid and efficient method for the synthesis of fused cyclopentenoids via Intramolecular Morita-Baylis-Hillman (IMBH) annulation. In this approach, copper triflate (Cu(OTf)) serves as the promoter, favoring cyclization and aromatization over the conventional MBH addition product. A characteristic feature among most of the cyclized product contain two non-separable isomeric mixture of cyclopentene derivatives which has been readily interconverted via 1,5-H shift.