Executive Summary : | Electrocyclic ring-closing reactions are an important class of pericyclic reactions for the formation of cyclic molecules. Since the formulation of Woodward-Hoffmann rules for the pericyclic reactions, significant developments have been made in the design and applications of 4-pi, 6-pi, and 8-pi electrocyclizations. However, the smallest possible 2-pi-electrocyclizations for the construction of three-membered rings remained largely unexplored. Moreover, the enantioselective 2-pi-electrocyclizations are not reported so far. Herein, we propose the development of a novel enantioselective 2-pi-electrocyclization reaction of vinyl carbenes derived from N-methoxypyridazinium salts (MOP-X), resulting in the chiral cyclopropenes. In addition, the synthetic utility of these cyclopropenes would be investigated in the photo-thermal pericyclic cascade reactions of MOP-X salts with 1,3-dienes/1,3-dipoles for the construction of bicyclo[4.1.0]heptane and azabicyclo[3.1.0]hexane containing carbo- and heterocycles with up to 5-contiguous stereocenters. The cyclopropane fused bicyclo[4.1.0]/[3.1.0] carbo- and heterocycles are present in many biologically relevant natural products and pharmaceuticals. Subsequently, the new scaffolds would be evaluated for the biological activity/medicinal chemistry applications. |