Thermal [2 + 2] cyclodimerisation of strained olefins. Cis, trans-1,5-cyclo-octadiene and trans-cyclo-octene
作者:Johannes Leitich
DOI:10.1016/0040-4020(82)85118-1
日期:1982.1
been investigated both with the racemic and with the optically active cycloolefins. Both title olefins form [2 + 2] dimers of the trans double bonds with complete retention of configuration (trans-syn-trans 2 by R + S and trans-anti-trans 3 by R + R combination) and with mono-inversion (cis,trans 4, both by R + S and R + R combinations), but almost none with di-inversion (cis-syn-cis 5 and cis-anti-cis
在外消旋体和旋光性环烯烃上均研究了在不存在催化剂的情况下的标题反应。两种标题烯烃均形成反式双键的[2 + 2]二聚体,具有完全保留的构型(R + S形成的反式-反式-反式 2和R + R组合产生的反式-反式-反式 3)并且具有单转化(顺式,反式 4,二者均由R + S和R + R的组合),但几乎与二反转无(顺式-顺式 5和顺-反-顺式 6),连同反式-顺式异构化的原料烯烃。