7-Methyl- and 7-phenylcyclohepta-1, 3, 5-trienes from benzvalene via 3, 3a, 4, 5, 6, 6a-hexahydro-4, 5, 6-methenocyclopentapyrazoles and tetracyclo[4. 1. 0. 0.0] heptanes
作者:Manfred Christl、Erich Brunn、Wolfgang R. Roth、Hans-Werner Lennartz
DOI:10.1016/s0040-4020(01)80119-8
日期:1989.1
norbornene with both diazoalkanes cannot be rationalized on the basis of frontier orbital energies. On direct photolysis, the pyrazolines 2a-g were converted into the tetracyclo[4. 1. 0. 02,4. 03,5] heptanes 4a-g exclusively. These compounds gave the 1, 3, 5-cycloheptatrienes 5a, b, d, e, g in high yields on treatment with silver ions, thus providing better access to 7, 7-dimethyl-(5d) and 7, 7-diphenylcycloheptatriene
向重氮甲烷,重氮乙烷,2-重氮丙烷,苯基重氮甲烷和二苯基重氮甲烷中添加苯并戊烯(1)以良好的收率得到1-吡唑啉2a-g。通过竞争实验,已经确定了苯并戊烯(1)和降冰片烯相对于重氮甲烷和2-重氮丙烷的相对反应性。苯并戊烯与两种重氮烷烃的反应速度约为降冰片烯的两倍,这不能基于前沿轨道能量来合理化。直接光解后,吡唑啉2a-g转化为四环[4]。1. 0. 0 2,4。0 3,5 ]庚烷4a-g只。在用银离子处理后,这些化合物可高收率地产生1,3,5-环庚烯5a,b,d,e,g,从而提供了更好的7、7-二甲基-(5d)和7,7-二苯基环庚三烯(5克)。出人意料的是,后一种化合物与大量的正十八碳烯形式处于平衡状态。-已经确定了4a至5a重排的反应热,这可以导出四环[4]的形成热。1. 0. 0 2,4。0 3,5 ]庚烷(4a)。