Dipolarophilic behaviour of the thiophene ring in intramolecular nitrile imine cycloadditions

Abstract

Unprecedented intramolecular nitrile imine cycloadditions onto a thiophene ring are described as a synthetic route to a number of tricyclic pyrazoline derivatives (5). Diadducts 6 and 7, which can be ascribed to a sequential intra–intermolecular cycloaddition pathway, are also formed.

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