A heteroditopic NHC and phosphine ligand supported ruthenium(<scp>ii</scp>)-complex: an effective catalyst for the <i>N</i>-alkylation of amides using alcohols
作者:S. N. R. Donthireddy、Vivek Kumar Singh、Arnab Rit
DOI:10.1039/d2cy00544a
日期:——
A ruthenium(II) complex of a chelated heteroditopic N-heterocycliccarbene ligand in combination with a phosphine ligand was uncovered to be a highly effective catalyst for the N-alkylation of diverse amides using readily available primaryalcohols. A wide range of secondary amides was thus obtained in excellent yields (up to 98%) employing a low catalyst (2c) loading of 0.2 mol% and a substoichiometric
发现螯合的杂二位N-杂环卡宾配体与膦配体的钌 ( II ) 配合物是使用现成的伯醇对各种酰胺进行N-烷基化的高效催化剂。因此,使用 0.2 mol% 的低催化剂 ( 2c ) 负载量和亚化学计量量的碱,以优异的产率(高达 98%)获得范围广泛的仲酰胺。1 H NMR 和 ESI - MS 分析支持N-杂环卡宾和磷化氢在催化循环中支持Ru-H物质,包括氘标记实验在内的机理研究表明涉及借氢方案。此外,目前的催化体系还被证明对 4-氨基苯甲酰胺的选择性单烷基化和不对称二烷基化是有效的,这在我们所知的范围内之前尚未研究过。
Nickel-Catalyzed Cross-Dehydrogenative Coupling of α-C(sp<sup>3</sup>)–H Bonds in <i>N</i>-Methylamides with C(sp<sup>3</sup>)–H Bonds in Cyclic Alkanes
作者:Ze-Lin Li、Kang-Kang Sun、Chun Cai
DOI:10.1021/acs.orglett.8b02736
日期:2018.10.19
A nickel-catalyzed cross-dehydrogenative coupling reaction of α-C(sp3)–H bonds in N-methylamides with C(sp3)–H bonds from cyclic alkanes has been developed, which offers a cheap transition-metal-catalyzed C–H activation method for amides without the requirement for any extraneous directing group. This new strategy is highly selective and tolerates a variety of functional groups. Mechanistic investigations