Heterocyclisation of ferrocenyl- and benzenetricarbonyl chromium-cyclopentadienes with o-quinone. Evidence for a SET route |
| |
Authors: | Mounia Joudat Annie Castel Fabien Delpech Heinz Gornitzka |
| |
Institution: | a Laboratoire d’Hétérochimie Fondamentale et Appliquée, UMR No. 5069, Université Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse cédex 4, France b Service Général de RMN, Université Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse cédex 4, France |
| |
Abstract: | A series of cyclopentadienyl ligands substituted by unsaturated systems including various transition metal groups ((C5H5)2Fe, PhCr(CO)3) were reacted with 3,5-di-tert-butyl orthoquinone producing 1,4-benzodioxines in high yields. These cycloaddition reactions were stereospecific. 1H and 13C NMR studies and X-ray structural analysis are in agreement with the exclusive formation of “endo” cycloadducts. Moreover, an ESR study shows the transient formation of both the radical anion of the o-quinone and the radical cation of the dienic system indicating an alternative single electron transfer pathway. |
| |
Keywords: | o-Quinones Cyclopentadienes Cycloaddition Diels-Alder SET reaction |
本文献已被 ScienceDirect 等数据库收录! |
|