13937-05-8Relevant articles and documents
ETUDE DE REACTIONS PAR TRANSFERT MONOELECTRONIQUE ENTRE DIVERS HYDROGERMANES A CARACTERE ACIDE ET DES SYSTEMES QUINONIQUES DIA- ET PARA-MAGNETIQUES
Riviere, P.,Castel, A.,Abdennadher, C.
, p. 181 - 194 (2007/10/02)
The chlorogermanes PhnCl3-nGe-H (n = 0, 1, 2) were treated with diamagnetic (3,5-di-t-butylorthoquinone) 1 and the paramagnetic galvinoxyl 2.These reactions occur mainly by monoelectron transfer giving the corresponding adducts.In the case of 3,5-di-t-butylorthoquinone, the resulting 1-4 adducts decompose by two simultaneous processes (HCl elimination and redistribution) yielding germadioxolanes.The chlorogermadioxolanes prepared in this way easily cause halogenic redistribution leading to chlorogermanes and germylcatecholates having branched or spiranestructure.In the case of the galvinoxyl radical, the same chlorogermanes lead by monoelectron transfer to the corresponding quinophenol and an intermediate germanium-centered radical.The latter by recombination outside the solvent cage, gives digermane.However, its primary reaction, which occurs within the solvent cage, is with quinophenol to form two isomeric O- and C-germylated catechols.The C-isomer is by far predominant as it also formed in the secondary hydrogermylation of quinophenol produced in the initial stage of the reaction.We have been able to confirm these mechanisms by a comparative study of the reaction of germanium hydrides R3Ge?+-H?-, acidic germanes X3Ge?--H?+, and germanates X3Ge(-)N-H(+) with galvinoxyl and the corresponding quinophenol.Key words: SET reactions; germylations; quinones; chlorohydrogermanes; chlorogermanes; chlorogermanates.
