Hexafluoroisopropanol has been demonstrated as the versatile promoter for redox-neutral α-C(sp3)-H functionalization of cyclic amines via the cascade [1,5]-hydride transfer/cyclization strategy. A wide range of cyclic amines are functionalized into bioactive tetrahydroquinolines, quinazolines, benzoxazines, and benzotriazepines in moderate to excellent yields. This protocol features additive-free conditions
A simple method for the synthesis of quinazolines was developed by exploiting the “tert-amino effect.” A catalytic amount of Brønsted acid (TsOH·H2O) worked as an effective activator for the concise construction of a quinazoline framework from o-formylaniline and amine.
Expedient Synthesis of 1,4‐Benzodiazepines via a Tandem Condensation/[1,5]‐Hydride Transfer/Cyclization Process
作者:Siyuan Liu、Tuan Zhao、Jingping Qu、Baomin Wang
DOI:10.1002/adsc.201800781
日期:2018.11.5
An expedient approach to 1,4‐benzodiazepines via a tandem condensation/[1,5]‐hydride shift/cyclization process has been developed. This transformation started from readily available o‐amino benzaldehyde and aminomalonate and was promoted by low‐cost FeCl3 with high step and atom economy.
Facile Formation of Cyclic Aminals through a Brønsted Acid-Promoted Redox Process
作者:Chen Zhang、Sandip Murarka、Daniel Seidel
DOI:10.1021/jo802325x
日期:2009.1.2
Cyclic aminals were prepared through a Bronsted acid-promoted reaction. This redox neutral process involves iminium ion formation, 1.5 H-transfer, followed by ring closure.