N-Chloroindole

Chlorination of indoles. The reaction of an aqueous solution of sodium hypochlorite with indole in pentane (or chloroform) at 0° (3 hr.) gives N-chloroindole (1) in 90-92% yield. This substance rearranges to 3-chloroindole (2) when heated in n-butanol containing potassium carbonate, possibly through (a)."... 

Indole (64) reacted with aqueous chlorine under mildly acidic conditions (Baben-zian et al., 1963 Lin and Carlson, 1984). The products are shown in Equation 5.28. The initial product formed is presumably N-chloroindole (DeRosa and Alonso, 1978). Carbazole (65) also reacted with free chlorine to produce a complex mixture of CI1-CI4 substitution products (Lin and Carlson, 1984). 

DeRosa, M. and J. L. T. Alonso. 1978. Studies of the mechanism of chlorination of indoles. Detection of N-chloroindole and 3-chloro-3H-indole as intermediates. J. Org. Chem. 43 2639-2643. 

Nitroso derivatives (120) are obtained from indoles they exist largely in oximino forms (121) (80IJC(B)767). The N-nitrosation of 5-chloroindole is followed by a migration of the nitroso group from N to C-3, to give an indolenine-3-oxime (122) hydrolysis and recyclization leads to a indazole carbaldehyde (123) (86JA4115). 

The treatment of isatin with sodium hypochlorite in acetic acid leads to 1-chloroisatin, an effective mild oxidizing agent for the conversion of alcohols to aldehydes and ketones110 and of indoles to 3-chloroindoles without formation of by-products111. N-[phenyliodine(III)] bisisatin can be obtained from the sodium salt of isatin and phenyliodine (IE) bistrifluoroacetate in 85% yield. This compound is a member of a group of iodine(III)imides,... 

Chloroindole)RuCp as well as (nitroindole)RuCp react with a variety of O, S, N, and C-nucleophiles to give substitution products [91]. One example of an enolate nucleophile effecting an intramolecular cyclization is shown in Eq. (22)... 

Nunthaboot N, Pianwanit S, Parasuk V, Kokpol S, Wolschann P (2007) Theoretical study on the HIV-1 integrase inhibitor l-(5-chloroindol-3-yl)-3-hydroxy-3-(2H-tetrazol-5-yl)-propenone (5CITEP). J Mol Struct 844-845 208-214. doi 10.1016/j.molstruc.2007.06.026... 

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