Abstract We report transamidation protocol to synthesize a range of secondary and tertiary amides from weakly nucleophilic aromatic and hetero-aryl amines with low reactive formamide derivatives, utilizing hydrochloric acid as catalyst. This current acid mediated strategy is beneficial because it eliminates the need for a metal catalyst, promoter or additives in the reaction, simplifies isolation and
An approach for N-formylation of amines was developed using NaBH(OAc)3 as a reductant under an atmosphericpressure of CO2 at 50 °C. The corresponding formylated products of various amines, including aliphatic and aromatic amines, amines with reductive-sensitive nitro groups and alkynyl groups and benzamides were obtained in good to excellent yields, and the possible reaction mechanism was also proposed
A simple catalyst- and additive-free method for the N-formylation of amines has been developed. The advantages of this protocol include a wide range of functional group tolerance, high efficiency and a lack of required extra promoters under mild conditions. This convenient strategy will provide a facile synthesis towards N-formamide natural products and pharmaceutical derivatives. A mechanism that involves difluorocarbene is proposed for this reaction. (C) 2019 Elsevier Ltd. All rights reserved.
US9682083B2
申请人:——
公开号:US9682083B2
公开(公告)日:2017-06-20
Facile Synthesis of Functionalized Bis(arylethynyl)benzene Derivatives via Sila–Sonogashira Reaction
Abstract This article describes a facile synthesis of a new series of symmetrical bis(arylethynyl)benzene derivatives via a one-pot coupling reaction between trialkylsilyl protected arylalkynyes and aryldihalides bearing both electron-withdrawing (EW) and electron-donating groups (ED) in the presence of PdCl2(PPh3)2(5%) / CuI/tetrabutylammonium fluoride / triethylamine / tetrahydrofuran (sila–Sonogashira