Chemoselective Acylation of Primary Amines and Amides with Potassium Acyltrifluoroborates under Acidic Conditions
作者:Alberto Osuna Gálvez、Cédric P. Schaack、Hidetoshi Noda、Jeffrey W. Bode
DOI:10.1021/jacs.7b00059
日期:2017.2.8
proceeds rapidly in water. The reaction is fast at acidic pH and tolerates alcohols, carboxylic acids, and even secondary amines in the substrates. It is applicable to the functionalization of primary amides, sulfonamides, and other N-functional groups that typically resist classical acylations and can be applied to late-stage functionalizations.
当前用于构建酰胺键的方法通过脱水偶联过程将胺和羧酸连接起来,该过程通常需要有机溶剂、昂贵且通常危险的偶联试剂,并掩盖其他官能团。在这里,我们描述了使用伯胺和酰基三氟硼酸钾的酰胺形成,由在水中快速进行的简单氯化剂促进。该反应在酸性 pH 值下很快,并且可以耐受底物中的醇、羧酸,甚至仲胺。它适用于伯酰胺、磺酰胺和其他通常抵抗经典酰化的 N 官能团的官能化,并可应用于后期官能化。
An efficient, eco-friendly and sustainable tandem oxidative amidation of alcohols with amines catalyzed by heteropolyanion-based ionic liquids via a bifunctional catalysis process
eco-friendly and sustainable method for the tandem oxidative amidation of alcohols with amines has been reported. Using heteropolyanion-based ionic liquids as the catalyst and tert-butyl hydroperoxide as the oxidant, this amidation reaction is operationally straightforward and provides a series of primary, secondary and tertiary amidesderivatives in moderate to good yields. Solvent-free media, microwave-promoted
Efficient Alkyl Ether Synthesis via Palladium-Catalyzed, Picolinamide-Directed Alkoxylation of Unactivated C(sp<sup>3</sup>)–H and C(sp<sup>2</sup>)–H Bonds at Remote Positions
作者:Shu-Yu Zhang、Gang He、Yingsheng Zhao、Kiwan Wright、William A. Nack、Gong Chen
DOI:10.1021/ja3023972
日期:2012.5.2
functionalization of unactivatedsp(3)- and sp(2)-hybridized C-H bonds. In the Pd(OAc)(2)-catalyzed, PhI(OAc)(2)-mediated reaction system, picolinamide-protected amine substrates undergo facile alkoxylation at the γ or δ positions with a range of alcohols, including t-BuOH, to give alkoxylated products. This method features a relatively broad substrate scope for amines and alcohols, inexpensive reagents
A Cu(OAc)2-mediated intramolecular aromatic C–H amination proceeds with the aid of a picolinamide-type bidentate coordination group to deliver the corresponding indolines in good yields. The reaction occurs smoothly even under noble-metal-free conditions, and in some cases the use of an MnO2 terminal oxidant renders the process catalytic in Cu. The mild oxidation aptitude of Cu(OAc)2 and/or MnO2 accommodates
Direct Amidation of Carboxylic Acids through an Active α-Acyl Enol Ester Intermediate
作者:Xianjun Xu、Huangdi Feng、Liliang Huang、Xiaohui Liu
DOI:10.1021/acs.joc.8b00819
日期:2018.8.3
The development of a highly efficient and simple protocol for the direct amidation of carboxylic acids is described employing ynoates as novel coupling reagents. The transformation proceeds in good to excellent yields via in situ α-acyl enol ester intermediatesformation under mild reaction conditions. This useful method has been demonstrated for a range of substrates to provide a succinct access to