Air- and Microwave-Stable (C5H5)Ru Catalysts for Improved Regio- and Enantioselective Carroll Rearrangements

摘要

Among the wide variety of synthetic methods allowing the construction of complex molecular structures, one of the best documented is the attack of a nucleophile at an allyl metal fragment, yielding chiral allylic compounds in (virtually) enantiopure form. One of the benefits of such substitution is that the regioselectivity of the reaction with unsymmetrical allyl substrates can be controlled by the metal catalyst. In this respect, several ruthenium-based compounds, in particular Cp~*Ru derivatives (Cp~* = C5Me5), have proven to be largely effective for the introduction of nucleophiles at the more substituted position, leading to branched (b) rather than linear (1) products [Eq. (1)] .