已经系统地研究了环丁二烯亲二烯(1)与环戊二烯酮的热环加成;立体异构体加合物可通过脱羰作用方便地获得各种四芳基-,甲基三苯基-,三苯基-,三叔丁基-和二甲基二苯基-环辛-1,3,5-三烯衍生物异戊二烯桥键合的价互变异构初级产物的开环,即。双环[4.2.0]辛二烯。这些化合物为研究电价互变异构体之间的平衡,热交联的范围和机理(例如不对称取代的环辛烯和热乙烯基-环丙烷(1,3-烯丙基转移)的异构化)提供了有用的模型。和/或所得芳基化的和烷基芳基二氢半bullvalenes的H原子转移歧化。该结果与环辛三烯-二氢半双戊烯转化和随后的重排的双自由基途径最相符。还报道了有用的13 C和1 H nmr结构相关性以及环戊二烯酮的新实例。
of tetranuclear Rh(I) and Ir(I) complexes. The tetra-NHC ligand displays axial chirality upon coordination to the MCl(cod) (M = Rh and Ir) fragments, giving rise to right- and left-handed helix conformations. The catalytic activity of the resulting complexes was studied in two relevant reactions that lead to the formation of five- and six-membered oxygen-containing heterocycles, namely, the cyclization
Synthese und oxidation von phenyl-substituierten resorcinen
作者:H. Güsten、G. Kirsch、D. Schulte-Frohlinde
DOI:10.1016/s0040-4020(01)96278-7
日期:1968.1
tetraphenylresorcinol, 2,4,6-triphenylresorcinol and 2,4-diphenylnaphthoresorcinol is described. During the oxidation of these phenyl-substituted resorcinols carbon monoxide is evolved followed by a ring contraction to phenyl-substituted cyclopentadienones. The deeply colored solutions obtained on oxidation give intensive ESR-signals with fine structure. We suggest that the reaction proceeds via a biradical