ABSTRAClPure 3-methylpentane was irradiated in its solid vitreous state a t 77 K. The qualitative analysis o f the dimeric products was made by mean of capillary chromatography coupled with m a s s spectrometry. The identification o f the dimers, highly branched dodecanes, required the synthesis o f compounds whose structure was defined by NMR13C DEPT ; they were characterised by their retention index measured a t several temperatures o n the capillary S E 3 0 column. h r o m a t o g r a p h i e -s p e c t r o m e t r i e de masse est generalement utilise pour l'identification desPour les dodecanes isomeres, les spectres de masse de reference font souvent defaut et de plus, en theorie, devraient etre tres semblabl e s .Si l'analyse de melanges d'hydrocarbures aliphatique pose en general de grandes difficultes, le probleme est encore complique par la presence d'alcenes, elles aussi tres ranifiees et presentes en traces dans l'alcane irradie. MCme l'efficacite des colonnes capillaires n'empeche pas la co-61ution.3 I1 n'est pas possible dans c e t article d e detailler tout le travail realise, un resume comprehensif est propose ; un document complet est disponible sur commande.6 I. Separation des produits satures et insatures. I.A. Inventaire des produits finals.combinaison deux a deux de quatre radicaux methyl-3 pentyle issus de la radiolyse du methyl-3 pentane : deux radicaux primaires R, et R4, un secondaire R2 et un tertiaire R3.Radio7 yse.

SUMMARYBenzyl chloride easily reacts with tin metal to yield dibenzyltin dichloride; no catalyst nor drastic conditions are needed to achieve the reaction. singularity has lead to propose benzyl chloride as a reagent for tin recovery (from tinplate8 e.g.1.However, benzyltin derivatives show poor performances as compared to butyltin compounds, especially from the point of view of phytopharmacy and PVC protection. butylaluminium increases the economic interest of the recovery process.

S t a b l e p r o d u c t s f r o m t h e p h o t o l y s i s o f HI i n m e t h y l -3 p e n t a n e ( 3 MP) o r d i m e t h y l -2 , 3 b u t a n e ( 2 3 DMB) q u e n c h e d s o l i d a t 7 7 K a r e a n a l y z e d b y c a p i l l a r y g a s c h r o m a t o g r a p h y . S e l e c t i v e f o r m a t i o n o f a t e r t i a r y r a d i c a l i s p r o p o s e d f o r t h e 23 DMB/HI s y s t e m ; i n 3 M P / H I , C -H b o n d r u p t u r e i s a l s o l o c a l i z e d a t t h e w e a k e s t t e r t i a r y b o n d , h o w e v e r t h e s c i s s i o n i s n o t s e l e c t i v e .