Reference

4-Haloindole derivatives

4-Haloindole derivatives. (Nissan Chemical Industries, Ltd., Japan). Jpn. Kokai Tokkyo Koho JP 58189162 A2 4 Nov 1983 Showa, 9 pp. (Japanese). 89434-04-8 and 52488-36-5 are also occured in this study. (Japan). CODEN: JKXXAF. CLASS: IC: C07D209-18. APPLICATION: JP 82-72628 30 Apr 1982. DOCUMENT TYPE: Patent CA Section: 27 (Heterocyclic Compounds (One Hetero Atom)) 4-Haloindole derivs. I (X = iodo, Br, Cl, F) were prepd. by, e.g., diazotization of 4-amino-1-(methoxycarbonyl)indole-3-acetonitrie (II), Sandmeyer reaction, and treatment of the resulting 4-halo-1-(methoxycarbonyl)indole-3-acetonitriles with alkali. Thus, 34.8 mg NaHNO2 in H2O was added to a mixt. of 50.4 mg II and 1.653 g 4.7% HBr in THF, the mixt. stirred 20 min at <5°, washed with cold CH2Cl2, stirred with 2 mL concd. aq. HBr contg. 674.3 mg CuBr 20 min at room temp., and boiled 5 min to give 82.1% 4-bromo-1-(methoxycarbonyl)indole-3-acetonitrile (III). Refluxing 28.2 mg III with 5 mL 40% aq. NaOH in MeOH 2 h gave 93.9% I (X = Br). .