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8215746 
Journal Article 
Competitive electron transfer and SN2 reactions of aromatic radical anions with alkyl halides and methanesulfonates 
Sã¸Rensen, HS; Daasbjerg, K 
1998 
Yes 
Acta Chemica Scandinavica
ISSN: 0904-213X
EISSN: 1902-3103 
Blackwell Munksgaard 
52 
51-61 
English 
The competition between electron transfer and SN2 processes in the reaction between a number of radical anions of aromatic compounds such as anthracene, pyrene, (E)-stilbene, m-tolunitrile and p-tolunitrile and different substrates such as the methyl, ethyl, butyl, 2-butyl, neopentyl and 1-adamantyl halides as well as methyl, ethyl, butyl and 2-butyl methanesulfonates has been investigated in N,N-dimethylformamide. By using the reaction of the radical anions with the appropriate alkyldimethylsulfonium iodide or trialkylsulfonium iodide as model for an electron transfer process the reaction mechanism could be characterized by electrochemical means in many of the cases listed. The presence of an SN2 component is found to be related not only to the steric requirements at the substrate but also to the magnitude of the driving force for the electron transfer process. In general, the higher the standard potential of the aromatic compound is or the poorer the substrate is as electron acceptor, the more important the SN2 mechanism becomes. An analysis of the substitution products obtained in the reaction between anthracene radical anion and the different substrates shows a considerable rise in the yield of the 9-alkyl-9,10-dihydroanthracene isomer as the magnitude of the SN2 component increases. © Acta Chemica Scandinavica 1998.