11. Direct halogenation of arenes are possible in the presence of light or at high temperature. 12. The original procedure involved halogenation of a sulfide, followed by oxidation to the sulfone. 13. Free radical halogenation typically produces a mixture of compounds mono-or multihalogenated at various positions. 14. Ethane can react with the halogens, especially chlorine and bromine, by free radical halogenation . 15. The putative halogenase Orf8 * has been proposed to catalyze the halogenation on both amino acids. 16. However, electrophilic substitution is relatively facile at the 5-position, including nitration and halogenation . 17. For alkylbenzene derivatives, the alkyl positions tend to be halogenated first in the free radical halogenation . 18. Cyclooctane participates in no reactions except those typical of other saturated hydrocarbons, combustion and free radical halogenation . 19. This compound may also be " cracked " to mononuclear Re ( I ) carbonyl complexes by halogenation : 20. Aryl chlorides may be prepared by the Friedel-Crafts halogenation , using chlorine and a Lewis acid catalyst.
