As a part of our ongoing research on the synthesis of bioactive constituents or molecules by using an organocatalytic approach, enantioselective total syntheses of ligraminol D and ligraminol E were achieved starting from a commercially available nonchiral aldehyde. Key steps in this synthesis were an asymmetric α-aminoxylation of an aldehyde and a Mitsunobu reaction.

A novel iron-catalyzed ring opening of cyclopropanols and their 1,6-conjugate addition to p-quinone methides for accessing substituted phenols is disclosed. In this protocol, various cyclopropanols are converted to alkyl radicals and undergo 1,6-conjugate addition to p-quinone methides toward C–C bond formation. The salient features of this methodology include operationally simple and mild reaction conditions, environmentally benign protocol, high efficiency, inexpensive catalyst, good to excellent yield, and a wide range of substrate scope.

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