Selective mono-chlorination of aromatic compounds under mild conditions bytert-butyl hypochlorite in the presence of zeolites

tert-Butyl hypochlorite/HNa faujasite X in acetonitrile represents an effic ient and highly regioselective system for mono-chlorination of a wide range of mono- and di-substituted aromatic substrates in mild conditions. Partia lly protonated faujasite X is far superior to amorphous silicas and to othe r zeolites in terms of efficiency and regioselectivity. Advantages of tert- butyl hypochlorite over other chlorinating reagents have been demonstrated. The method is suitable for large scale work.