2 - 芳基 -4- 苯基 -2, 3- 二氢 -1, 5- 苯并二氮杂卓与重氮乙酸乙酯反应机 理和 立体化学的研究

2-芳基-4-苯基-2,3-二氢-1,5-苯并二氮杂卓与重氮乙酸乙酯在铜粉催化下反应，得到环加成产物吖丙啶并苯并二氮杂卓I外，还得到一个非预期的五员环产物吡咯并苯并二氮杂卓II。改变反应条件可以使化合物II的收率达到50%。通过研究反应过程中分离出的副产物反丁烯酸二乙酯III和4,5-二氢吡唑-3,4,5-三羧酸乙酯IV,初步提出了反应经过乙氧羰基甲基化苯并二氮杂卓翁中间体V再发生环加成反应的机制。通过X-射线单晶衍射分析和NMR分析研究了它们的立体化学，发现为立体专一性反应。

Studies on the mechanism and stereochemistry of the reaction of 2- phenyl-4- aryl-2,3-dihydro-1, 5-benzodiazepine with ethyl diazoacetate

The reaction of 2 - phenyl - 4 - aryl -2,3- dihydro -1,5- benzodiazepine with ethyl diazoacetate using power Cu as a catalyst gives a normal cycloaddition product , azirino - benzodiazepine (I) , and an unprecedent product pyrro - benzodiazepine (II) . The yield of (II) was increased to 50% under the optimum condition. From the studies of the side - products diethyl fumarate (HI) and ethyl 4,5 - dihydropyrazole - 3,4,5 - tricarboxylate (IV) , the reaction mechanism , which involved formation of benzodiazepinium ethoxycarbonylmethylate (V) followed by cycloaddition reaction , was tentatively proposed. The reaction was proved to be stereospecific based on the analysis of X - ray and NMR spectra.