Inert C–H Bond Transformations Enabled by Organometallic Manganese Catalysis

• DOI: 10.1021/acs.accounts.8b00028
• Publication Date: 2018-02-14T21:43:05Z
• Authors: Yuanyuan Hu; Bingwei Zhou; Congyang Wang
• Keywords: Inert; Organometallic Chemistry

ConspectusTraditional organic synthesis relies heavily on the transformations of various preinstalled functional groups, such as cross-coupling reactions using organohalides and organometallic reagents. The strategy C–H activation enables direct formation C–C/C–X (X = heteroatom) bonds from inert bonds, which can enhance atom- step-economy synthesis. To date, precious metals have overwhelmingly dominated field; however, rarity high cost these necessitate development more sustainable catalysts. In this regard, catalysts based manganese are highly desirable owing to abundant reserve in earth's crust its economic benefits, low toxicity, potentially unique reactivity. Although first stoichiometric manganese-mediated reaction was reported early 1970, manganese-catalyzed largely underdeveloped. How construct an efficient catalytic cycle for remains a key issue be addressed.In Account, we summarize our recent advances bonds. overcome challenges associated with building manganese-based cycles, developed two novel strategies, namely, synergy between bases (with or w/o bases) acids. By implementing former strategy, cooperative manganese/base systems that facilitate new mode bond by via redox-neutral base-assisted deprotonation mechanism. As such, requirement tedious preparation MnR(CO)5 complexes (R Me, Bn, Ph) eliminated, series arenes partners having C≡C C═C were achieved. Through latter acids, disclosed "dual activation" performing transformations, is, merging C–X multiple Lewis Consequently, scope substrates could expanded include challenging ketones olefinic compounds. Additionally, range significantly broadened those bearing polarized C═O, C═N, C≡N aldehydes, imines, nitriles. Remarkably, innate reactivity different reversed catalysis, even carried out at room temperature. Our findings provide guiding information future beyond. Related important contributions other groups mentioned, remaining perspective emerging area also presented.