1. Fe(CO)5, Mn2(CO)10, and Mo(CO)6 in combination with DMF initiate the conversion of 1,3,3,5-tetrachloropentane to 1,3,5-trichloropentane and 1,3,5-trichloro-2-pentene. 2. The Fe(CO)5+DMF system initiates the conversion of 1,3,3,5-tetrachloropentane to 1,3,5-trichloropentane via the formation of the CH2ClCH2CClCH2CH2Cl radicals and the preferential cleavage of H atoms from a hydrogen donor by these radicals. 3. In the presence of Mn2(CO)10 and Mo(CO)6 in combination with DMF the ClCH2CH2CClCH2CH2C1 radicals disproportionate to give 1,3,5-trichloropentane and 1,3,5-trichloro-2-pentene.