Ruthenium PNP pincer complexes bearing supplementary cyclometalated C,N-bound ligands have been prepared and fully characterized for the first time. By replacing CO and H- as ancillary ligands in such complexes, additional electronic and steric modifications of this topical class of catalysts are possible. The advantages of the new catalysts are demonstrated in the general α-alkylation of ketones with
Cobalt-Catalyzed Enantioconvergent Hydrogenation of Minimally Functionalized Isomeric Olefins
作者:Peng Lu、Hongliang Wang、Yihui Mao、Xin Hong、Zhan Lu
DOI:10.1021/jacs.2c08525
日期:2022.9.28
established methods often require geometrically pure olefins. The enantioconvergent reaction provided the possibility to access a single stereoisomer via hydrogenation of E/Z-olefin mixtures; however, a polar functional group next to the carbon–carbon double bond was usually necessary. Here, we reported a cobalt-catalyzed enantioconvergent hydrogenation of readily available minimally functionalized E/Z-olefin
由于对映体纯化合物的高需求,烯烃不对称氢化的研究在药物分子合成和化学工业中都具有重要意义。已建立的方法通常需要几何纯烯烃。对映收敛反应提供了通过氢化E / Z -烯烃混合物获得单一立体异构体的可能性;然而,通常需要在碳-碳双键旁边的极性官能团。在这里,我们报道了一种钴催化的对映收敛氢化容易获得的最小官能化E / Z-烯烃混合物。该策略显示出良好的官能团耐受性,并为对映收敛转化提供了一种替代方法。初步机理研究表明,钴催化异构化是实现收敛转化的关键。
Selective nickel-electrocatalyzed benzylic C–H oxygenation of functionalized alkyl arenes
provides a safe, green and economical method for oxidation of a range of molecules varying in complexity and drug derivatives, demonstrating its potential application in organic synthesis and the pharmaceutical industry. Reaction outcomes and mechanistic studies revealed the key role of the in situ Ni(II)-dioxygen species for the subsequent oxidation of C(sp3)–H bonds, and short-lived reactive intermediates
A photoinduced nickel-catalyzed reductive carbonylative coupling from organohalides and N-(acyloxy)phthalimide esters with phenyl formate as the carbonyl source has been developed. This reaction could perform smoothly under mild conditions, and a series of aryl–alkyl and alkyl–alkyl unsymmetrical ketones were produced without the need of stoichiometric metal reductants. Mechanistic studies indicate