Direct Amidation of Carboxylic Acids Catalyzed by <i>ortho</i>-Iodo Arylboronic Acids: Catalyst Optimization, Scope, and Preliminary Mechanistic Study Supporting a Peculiar Halogen Acceleration Effect
作者:Nicolas Gernigon、Raed M. Al-Zoubi、Dennis G. Hall
DOI:10.1021/jo3013258
日期:2012.10.5
synthetic products motivates the development of catalytic, direct amidation methods employing free carboxylic acids and amines that circumvent the need for stoichiometric activation or coupling reagents. ortho-Iodophenylboronic acid 4a has recently been shown to catalyze direct amidation reactions at room temperature in the presence of 4A molecularsieves as dehydrating agent. Herein, the arene core of ortho-iodoarylboronic
Boronic Acid Catalysts and Methods of Use Thereof for Activation and Transformation of Carboxylic Acids
申请人:Hall Dennis
公开号:US20140142322A1
公开(公告)日:2014-05-22
The present application provides methods and catalysts for activation of carboxylic acids for organic reactions. In particular, methods are disclosed for direct nucleophilic addition reactions, such as, amidation reactions with amines, cycloadditions, and conjugate additions, using boronic acid catalysts of formula I, II or III: Also included are novel boronic acid catalysts of formula IV, V and III:
Catalytic Chemical Amide Synthesis at Room Temperature: One More Step Toward Peptide Synthesis
作者:Tharwat Mohy El Dine、William Erb、Yohann Berhault、Jacques Rouden、Jérôme Blanchet
DOI:10.1021/acs.joc.5b00378
日期:2015.5.1
An efficient method has been developed for direct amide bond synthesis between carboxylic acids and amines via (2-(thiophen-2-ylmethyl)phenyl)boronic acid as a highly active bench-stable catalyst. This catalyst was found to be very effective at room temperature for a large range of substrates with slightly higher temperatures required for challenging ones. This methodology can be applied to aliphatic
A conceptually new strategy has been described for the mild and environmentally friendly preparation of β-naphthylamines via Tf2O-activated cyclization of amides with alkynes. Both terminal and internal alkynes could serve as effective nucleophiles in this transformation. This chemistry features simple reaction conditions, high chemoselectivities, wide substrate scope, and offers a practical approach
已经描述了一种概念上的新策略,用于通过酰胺与炔烃的 Tf 2 O 活化环化来温和且环保地制备 β-萘胺。末端和内部炔烃都可以作为这种转化中的有效亲核试剂。该化学反应条件简单、化学选择性高、底物范围广,为多取代的β-萘胺提供了一种实用的方法。