By-side impurities in chloronaphthalene mixtures of the Halowax series: all 12 chlorobenzenes.

Total chlorobenzene content of the Halowax mixtures ranged from 1100 to 9800 ng/g. A lower chlorinated Halowax 1031 and 1000 were a several times more contaminated with chlorobenzenes than higher chlorinated Halowax 1001, 1099, 1013, 1014, or 1051. Depending on the type of the Halowax mixture the most contributing amongst of chlorobenzene homologue groups were di-, tetra-, penta-, and hexa-CBz. A dominance and specific profile of 1,4-DiCBz, PeCBz, and HCBz were characteristic to Halowax 1001, 1099, 1013, 1014, and 1051, while for other formulation the CBzs profile varied, and 1,2,3,4-TeCBz (Halowax 1031) and 1,4-DiCBz (Halowax 1000) predominated. A steric hindrance effect seems to direct a preferential by-side formation of 1,4-DiCBz and further also of PeCBz and HCBz due to relatively elevated temperature as well as duration time of synthesis for five most chlorinated (49-70 Cl%) chloronaphthalene Halowax formulations.