CHARGE-TRANSFER COMPLEXES IN ADDITION-REACTIONS OF CBR4 TO UNSATURATED-COMPOUNDS INITIATED BY FE(CO)5 SYSTEMS

The changes in the electronic absorption spectra of charge transfer complexes (CTC) formed in Fe(CO)5 initiation systems qualitatively correlate with the activity of these systems in the initiated homolytic addition of CBr4 to 1-hexene, methyl acrylate, and vinyltrimethylsilane. The formation of an Fe-(CO)4-olefin pi-complex is not observed in the reaction of methyl acrylate with CBr4, while the generation of tribromomethyl radicals occurs in a complex CTC, apparently containing all the reaction components, namely, the addend, monomer, Fe(CO)5, and coinitiator. These data show that the study of CTC of Fe(CO)5 initiation systems may be useful for predicting their activity in homolytic addition and telomerization reactions involving halogen-containing addends.