INVESTIGATIONS OF THE STRUCTURE AND REACTIONS OF THE INTERMEDIATE IN THE CHLORINATION OF RESORCINOL

The investigation reported here describes an attempt to establish the structure of the intermediate that undergoes ring-opening in the chlor ination of resorcinol and its chloro-derivatives in a nucleophilic sol vent such as H2O or CH3OH. The evidence suggests that the pentachlorid e and not the tetrachloride is the intermediate that reacts with the n ucleophiles. Chlorination reactions were conducted in CH3OH/H2O. The s tructures of the ''early-generation'' products from incorporation of C H3OH were sufficiently stable to be characterized. These products impl icated the pentachloride. Resorcinol, di- and trichlororesorcinol, and the pentachloride gave the same products. The mechanisms of the ring- opening and the reactions leading to the products are described in det ail. The assumption is made that the same or similar reactions are inv olved in the aqueous chlorination of resorcinol, but that decarboxylat ion and solvolysis reactions rapidly degrade the products immediately following ring-opening.