A series of N-monoalkyl aromatic amines are synthesized in high yields from corresponding nitroarene derivatives,aldehydes,and ammonium formate in the presence of Pd/C as a catalyst through one-pot operations at room temperature. Both the conversion and selectivity of the process are above 80%. Optimum reaction conditions are investigated,and it is found that the optimum molar ratio of nitroarene derivatives to ammonium formate and the optimum weight ratio of nitroarene derivatives to Pd/C are 1/4 and 1/0.10,respectively. These experiments provide a novel access for N-monoalkyl aromatic amines with advantages of simplicity,high selectivity,and environmental benignity.
Under the high-speed vibration milling conditions,the solvent and catalyst-free azo-Michael addition of chalcone derivatives and amines was found to proceed efficiently in excellent yields at ambient temperature in short reaction time.In most cases,conventional side reactions were avoided and thus quantitative yields were achieved.The influences of the vibration frequency and reaction time on the azo-Michael addition were investigated.
LI YuJinCAO YongWenXU FengShuangFANG WenMingYU WuBinJIA JianHongGAO JianRong
An aqueous solution of hydrogen peroxide and hydrogen bromide illuminated by a 60 W incandescent light bulb serves as a source of bromine radicals.Various substituted toluenes(NO_2,Cl,Br,H,CH_3) were high selectively brominated at the benzyl position for monobromination in CH_2C1_2 at ice water with catalyst free.This simple but effective bromination of toluene derivatives with an aqueous H_2O_2-HBr system is characterized with the use of inexpensive reagents and a lower impact on the environment, which make it a good alternative to the existing bromination methods.
Jie Ju Yu Jin Li Jian Rong Gao Jian Hong Jia Liang Han Wei Jian Sheng Yi Xia Jia
