Study On The Synthesis Of Heterocyclic α-Amino Phosphonates And 1, 5-Benzodiazepines Catalyzed By Lanthanide Chlorides

The reaction towards synthesis of novel cyclicα-amino phosphonates and 1,5-benzodiazepines using lanthanide chlorides as catalyst were studied in this thesis:1. The cyclicα-amino phosphonates were efficiently synthesized by the one-pot reaction of o-phenylenediamines, ketones orα,β-unsaturated ketones and phosphites catalyzed by ytterbium chlorides (YbCl3). The reaction was carried out under mild and solvent-free conditions affording the desired products in moderate to excellent yields. The substitution of the heterocycle in different position was successfully achieved using differentα,β-unsaturated ketones. The mechanism of the present reaction was also proposed.2. The 1,5-benzodiazepines, which was suggested to be the intermediate in above reaction, were prepared in low to excellent yields in the reaction of o-phenylenediamine with ketones orα,β-unsaturated ketones efficiently catalyzed by lanthanide chlorides under mild conditions. YbCl3 was found to be water-tolerant and could be recovered and reused.In addition, the carbon-oxygen coupling reaction catalyzed by Ni(0)-NHC was explored. The intermediate Ni(0)-NHC generated in situ from Ni(acac)2 and imidazolium effectively catalyzed the carbon-oxygen bond formation in the reaction of aryl halides with alcohols and tert-butyl aryl ether was obtained.