Photoinduced electron transfer from chloropromazine and promethazine to chloroalkanes accompanied by cleavage of C-Cl bond

Electron transfer from two phenothiazine derivatives namely promethazine an d chloropromazine to chloroalkanes namely carbontetrachloride and chlorofor m has been studied by steady state fluorescence and transient absorption te chniques. These phenothiazine derivatives also form weak charge transfer co mplexes with the above two chloroalkanes. Picosecond transient absorption s tudies provide direct evidence for two processes: (1) charge separation in the charge transfer complex and (2) electron transfer from the excited stat e of phenothiazines to chloroalkanes. A modified Marcus electron transfer t heory proposed by Saveant [J. Am. Chem. Soc. 109 (1987) 6788], which incorp orates the bond cleavage, has been used to explain the observed experimenta l results. (C) 2001 Elsevier Science B.V. All rights reserved.