F-19 NMR spectroscopy of polyhalonaphthalenes Part V. Halex reactions of polychloroisoquinolines

Nucleophilic fluoride fluoro-dechlorination of four isoquinolines (5,6,7,8- tetrachloro-,3,5,6,7,8-pentachloro-3,4,5,6,7,8-hexachloro- and 1,3,4,5,6,7, 8-heptachloro-isoquinoline) led to the preparation of 15 new polychloropoly fluoro isoquinolines by reaction with caesium fluoride in DMSO at 100 degre es C. The product from the perchloroisoquinoline was an inseparable mixture of C9Cl7-nFnN where n is 1-3. The order of reactivity in 1,3,3,5,6,7,8-hep tachloro-isoquinoline [10] to nucleophilic attack by fluoride was 1 much gr eater than 6 = 7 = 8 > 3 = 5 > 4 (C) 2000 Elsevier Science S.A. All rights reserved.