Highly Efficient Rh(I) Homo- and Heterogeneous Catalysts for C–N Couplings via Hydrogen Borrowing
作者:Chin M. Wong、Matthew B. Peterson、Indrek Pernik、Roy T. McBurney、Barbara A. Messerle
DOI:10.1021/acs.inorgchem.7b02586
日期:2017.12.4
explored as catalysts for the hydrogenborrowing reactions of amines and alcohols. Bidentate carbene-triazole ligands were readily synthesized via “click” reactions which allowed a diversity of ligand backbones to be accessed. The catalytic transformations are highly efficient, able to reach completion in under 6 h, and promote C–N bond formation across a range of primary alcohol and amine substrates. Moreover
for the alkylation of amines using alcohols as alkylating agents. Catalysts 1, 2 and 3a gave excellent yields of up to 99% for the alkylation of various amines using benzylic and aliphatic alcohols at 130 °C for 18 h undersolventlessconditions. Catalyst 3a bearing both phosphine and carbene ligands gave excellent yields of up to 98% for the synthesis of heterocyclic amines by double alkylation of primary
Rh-catalyzed aerobic oxidative cyclization of anilines, alkynes, and CO
作者:Xinyao Li、Jun Pan、Hao Wu、Ning Jiao
DOI:10.1039/c7sc02181j
日期:——
Transition-metal-catalyzed oxidative C-H cyclization of anilines has been an attractive and powerful strategy for the efficient construction of N-heterocycles. However, the primary and tertiary anilines are rarely employed in this strategy due to the relatively unstability with strong oxidants or the presence of three C-N bonds. By using aerobic oxidative protocol, we describe here a novel Rh-catalyzed
Iridium(<scp>iii</scp>) homo- and heterogeneous catalysed hydrogen borrowing C–N bond formation
作者:Chin M. Wong、Roy T. McBurney、Samantha C. Binding、Matthew B. Peterson、Vinicius R. Gonçales、J. Justin Gooding、Barbara A. Messerle
DOI:10.1039/c7gc01007a
日期:——
excellent homogeneous catalysts for the hydrogenborrowing mediated coupling of alcohols with amines. The reactions are highly efficient, able to reach completion in under 6 h at 100 °C at low catalyst loadings of 0.5 mol%, and are environmentally benign, the only by-product is water. The Ir(III) catalysts promoted C–N bond formation across a range of alcohol and amine substrates, including biologically
二齿卡宾-三唑配体的五甲基环戊二烯基铱(III)配合物是氢借位介导的醇与胺偶联的优良均相催化剂。反应是高效的,在0.5 mol%的低催化剂负载下,在100°C下可在6小时内完成反应,而且对环境无害,唯一的副产物是水。铱(III)催化剂促进了一系列醇和胺底物(包括生物学相关基序)上C–N键的形成。与炭黑表面的共价连接产生了定义明确的“杂化”非均相催化剂,该催化剂在苯胺与苄醇的偶联反应中具有良好的转化成产物的能力,并且可以在没有催化剂浸出的情况下进行再循环。这代表了用于氢借用的碳上共价连接的异质铱催化剂的首次报道。发现非均相的周转数(TON)明显高于相应的均相反应。为了阐明均相反应机理,结合氘化实验的1 H NMR研究提出了一种机理。
Cross dehydrogenative coupling strategy for allylation of benzylanilines promoted by DDQ
A cross dehydrogenative coupling strategy for allylation of benzylanilines promoted by DDQ is reported, which uses nonmetallic quinone DDQ as an oxidant in the allylation of N-benzylanilines under mild conditions. C–C bond with high selectivity and activity was constructed in this reaction and homoallylic amines were obtained with yields of up to 99%.