Several investigations into regio-, diastereo-, and enantioselective transformations of zirconocene imido complexes and their products have been proposed (2+2) cycloaddition of allylimido zirconium complexes with allenes and/or alkynes, followed by (3,3) sigmatropic rearrangement, has the potential for highly regio- and diastereoselective functionalization of simple organic compounds. The overall process is the formal addition of amino and allyl groups across a carbon-carbon multiple bond. Subsequent functionalization or rearrangement would yield an array of complex organic products from simple starting materials. An enantioselective desymmetrization of meso epoxides and/or aziridines is also described that would result in production of chiral allyl alcohols and amines or chiral amino alcohols and diamines. Finally, mechanistic determination of the electronic influence of the metallocene and the nitrogen substituents of zirconocene imido complexes on the (2+2) cycloaddition reaction with simple alkenes will shed light on the origin of the high reactivity of this system and possibly elucidate methods for enhancing or tuning that reactivity.
