A Concerted Transfer Hydrogenolysis: 1,3,2-Diazaphospholene-Catalyzed Hydrogenation of NN Bond with Ammonia-Borane
作者:Che Chang Chong、Hajime Hirao、Rei Kinjo
DOI:10.1002/anie.201400099
日期:2014.3.24
1,3,2‐diazaphospholenescatalyzemetal‐free transfer hydrogenation of a NN double bond using ammonia–borane under mild reaction conditions, thus allowing access to various hydrazine derivatives. Kinetic and computational studies revealed that the rate‐determining step involves simultaneous breakage of the BH and NH bonds of ammonia–borane. The reaction is therefore viewed as a concerted type of
Base-Catalyzed Hydrophosphination of Azobenzenes with Diarylphosphine Oxides: A Precise Construction of N-N-P Unit
作者:Gang Hong、Xiaoyan Zhu、Chen Hu、Alfred Njasotapher Aruma、Shengying Wu、Limin Wang
DOI:10.1021/acs.joc.6b01210
日期:2016.8.5
Addition of diarylphosphine oxides to the N═N double bond of azobenzenes leads to the formation of the P-substituted hydrazines in up to 98% yield for 24 examples, and the formation of diphenylphosphinic amides was observed in three substrates. This strategy features tolerance of a wide range of functional groups, simple operation, and mild reaction conditions. Specially, this method can be also applied
<i>N</i>,<i>N</i>-Diisopropylethylamine-Mediated Electrochemical Reduction of Azobenzenes in Dichloromethane
作者:Hongyan Zhou、Rundong Fan、Jingya Yang、Ximei Sun、Xiaojun Liu、Xi-Cun Wang
DOI:10.1021/acs.joc.2c01949
日期:2022.11.4
report a cathodic reduction-dominated electrochemical approach for the hydrogenation of azobenzenes in dichloromethane. With cheap and readily available N,N-diisopropylethylamine as a catalytic mediator, the reaction proceeded smoothly in a simple undivided cell under constant-current electrolysis. A series of azobenzenes were successfully reduced to the corresponding hydrazobenzenes in moderate to high
Minute amounts of supported Au nanoparticles on TiO2 (0.1 mol%) catalyze quantitatively at room temperature the transferhydrogenation of azoarenes to hydrazoarenes by ammoniaborane complex, in ethanol as solvent. At 1 mol% catalyst loading level and 2.5 molar equivalents of ammoniaborane the process occurs instantaneously. The catalyst is recyclable and reusable. In the absence of reducing agent,
TiO 2上的微量负载Au纳米颗粒(0.1 mol%)在室温下定量催化在乙醇作为溶剂中通过氨硼烷络合物将偶氮芳烃转移氢化为腙芳烃。在 1 mol% 催化剂负载水平和 2.5 摩尔当量氨硼烷下,该过程立即发生。该催化剂可回收、可重复使用。在没有还原剂的情况下,亚氮芳烃经历顺利的Au/TiO 2催化的有氧氧化回到偶氮芳烃。