摘要
首次以 Ph3P-C2 Cl6 为氯化试剂 ,从 2 -苄基苯甲酰肼制备了苯甲酰氯苄基腙 ,再在三乙胺的存在下 ,通过生成腈亚胺 ( nitrilimine)偶极体的中间态 ,原位与反式的肉桂酸乙酯发生 1 ,3 -偶极环加成反应生成 4 ,5-反式 -1 -苄基 -3 ,5( 4) -二苯基 -Δ2 -吡唑啉 -4 ( 5) -羧酸乙酯。反应的方位选择性用前线轨道 ( FMO)理论进行了解释。
N Benzylbenzhydrazonyl chloride(13) was prepared from N benzyl N′ benzoylhydrazine with Ph 3P C 2Cl 6 as chlorinating agent for the first time. In the presence of trans ethyl cinnamate, the \%in situ\% generated N benzyl C phenyl nitrilimine by the dehydrochlorination of compound 13 by triethylamine afforded trans ethyl 4,5 dihydro 1 benzyl 3,5 diphenyl 4 pyrazole carboxylate(14) and trans ethyl 4,5 dihydro 1 benzyl 3,4 diphenyl 5 pyrazole carboxylate(15). The regioselectivity observed in the reaction was explained in terms of FMO theory.
出处
《中国药科大学学报》
CAS
CSCD
北大核心
2000年第4期241-245,共5页
Journal of China Pharmaceutical University
关键词
偶极环加成反应
腈亚胺
△^2吡唑啉羧酸
合成
WT5,5”BZ]Dipolar cycloaddition
N Benzyl C phenylnitrilimine
Δ~2-Pyrazoline carboxylic acid derivatives