<i>ortho</i>
-Directing Chromium Arene Complexes as Efficient Mediators for Enantiospecific C(sp<sup>2</sup>
)-C(sp<sup>3</sup>
) Cross-Coupling Reactions
作者:Raphael Bigler、Varinder K. Aggarwal
DOI:10.1002/anie.201711816
日期:2018.1.22
ortho‐lithiation of chromium arene complexes followed by boronate formation and oxidation, occurs with complete ortho‐selectivity and enantiospecificity to give the coupling products in excellent yields and with high functional group tolerance. An intermediate chromium arene boronate complex was characterized by X‐ray, NMR, and IR experiments to elucidate the reaction mechanism.
Two variants of synthesis of resveratrol (3,5,4'-trans-trihydroxystilbene) from dimethyl ether and anisaidehyde were performed using the chromium eta(6)-benzenetricarbonyl complex. The Wittig-Horner reactions or aldol condensation in four stages followed by demethylation by EtSLi were applied.