作者:D. Cristina、M. De Amici、C. De Micheli、R. Gandolfi
DOI:10.1016/s0040-4020(01)92451-2
日期:1981.1
2-diazopropane and C-pnenyl-N-methyl-nitrone react with the sole tetrasubstituted double bond of 1a–c in stereo- and site-specific cycloadditions. The quantitative evaluation of the two possible reaction paths was performed by glc analysis. The compounds detected were those arising from Diels-Alder cycloreversions of the thermally labile intermediate adducts 2 and 3 (Scheme 1). The results were rationalized
芳基叠氮化物,苄腈氧化物和二苯基腈亚胺与降冰片二烯衍生物1a–c的环加成反应显示出不同程度的位点和立体选择性。对于双极性亲和剂1a,芳基叠氮化物和苯甲腈氧化物优先攻击电子贫的四取代双键,而在1b和1c的情况下,则是进入环加成的取代双键。相比之下,2-重氮丙烷和C-亚苯基-N-甲基-硝基与立体和位点特定的环加成反应中与1a–c的唯一四取代双键反应。通过glc对两种可能的反应路径进行定量评估分析。检测到的化合物是由热不稳定的中间体加合物2和3的Diels-Alder环还原所产生的化合物(方案1)。在仅考虑边界轨道相互作用的定性摄动处理的基础上,对结果进行了合理化。