A method for synthesizing six-membered heterocycliccompounds was developed based on the features of O,P-acetals. Sequential reactions of intramolecular cyclization between the methylene carbon atom of O,P-acetal and its electrophilic functional group (ester or protected carbamate) was followed by Horner–Wadsworth–Emmons (HWE) olefination with various aldehydes. The developed one-pot method yielded
Efficient and chemoselective direct reductive amination of aromatic aldehydes catalyzed by oxo–rhenium complexes containing heterocyclic ligands
作者:Joana R. Bernardo、Sara C.A. Sousa、Pedro R. Florindo、Mariusz Wolff、Barbara Machura、Ana C. Fernandes
DOI:10.1016/j.tet.2013.08.016
日期:2013.10
This work describes the catalytic activity of 17 oxo–rhenium complexescontainingheterocyclicligands in the direct reductive amination of 4-nitrobenzaldehyde with 4-chloroaniline, using phenylsilane as reducing agent. In general, all of the catalysts tested gave excellent yields of the secondary amine, although, the best result was obtained with the catalytic system PhSiH3/ReOBr2(Hhmpbta)(PPh3) (2
Efficient and Highly Chemoselective Direct Reductive Amination of Aldehydes using the System Silane/Oxorhenium Complexes
作者:Sara C. A. Sousa、Ana C. Fernandes
DOI:10.1002/adsc.201000246
日期:2010.9.10
This work reports a novel method for direct reductive amination of aldehydes with silanes catalyzed by several high‐valent oxorhenium(V) and oxorhenium(VII) complexes. The catalytic system PhSiH3/ReIO2(PPh3)2 (2.5 mol%) was very efficient for the synthesis of secondary amines and highly chemoselective, tolerating a wide range of functional groups such as NO2, CF3, SO2R, CO2R, F, Cl, Br, I,
这项工作报告了一种新颖的方法,该方法通过几种高价的氧化or(V)和氧化or(VII)络合物催化的硅烷与硅烷直接还原胺化。催化体系PhSiH 3 /一体化组织2(PPH 3)2(2.5摩尔%)是仲胺的合成非常有效和高度化学选择性,容忍一个宽范围的官能团如 NO 2, CF 3, SO 2 R, CO 2 R,楼氯, BR, I,CN, OH, OCH 3, SCH 3, NCOR,和双键。该新方法还用于中等产率的叔胺合成中。