37914-61-7Relevant articles and documents
C-2 SIDE CHAIN ALKYLATION OF 2-METHYL-3-ALKYLINDOLES VIA 3-METHOXYINDOLENINES
Vice, Susan F.,Gross, Edward A.,Friesen, Richard W.,Dmitrienko, Gary I.
, p. 829 - 832 (2007/10/02)
3-Methoxyindolenines derived from 2-methyl-3-alkylindoles by bromination-methanolysis undergo base induced alkylation and aldol condensations at the C-2 methyl group.The modified indolenines can be efficiently converted to C-2-side chain alkylated indoles
The bromination and chlorination of 2,3-dialkylindoles. Isolation of 3-bromo- and 3-chloro-2,3-dialkylindolenines and acid catalyzed conversion to 3-methoxyindolenines
Dmitrienko, Gary I.,Gross, Edward A.,Vice, Susan F.
, p. 808 - 814 (2007/10/02)
The bromination of 2,3-dimethylindole in acetic acid followed by hydrolysis has been shown to yield the known dimer 16 of 3-hydroxy-2,3-dimethylindolenine 15 and not 3-hydroxymethyl-2-methylindole 12 as reported previously by others.Bromination of 2,3-dimethylindole in the presence of triethylamine has yielded 3-bromo-2,3-dimethylindolenine 17 as a crystalline solid which is stable at room temperature in a nitrogen atmosphere in the presence of triethylamine but decomposes vigorously in the absence of base.Under mildly acidic conditions 17 reacts rapidly with methanol to yield 3-methoxy-2,3-dimethylindolenine 3 in good yield.With tert-butyl hypochlorite in the presence of triethylamine, 2,3-dimethylindole gives 3-chloro-2,3-dimethylindolenine 2 which has chemical properties similar to 17 reacting readily with methanol to give 3.Similarly tetrahydrocarbazole was converted to the analogous chloroindolenine 5 and bromoindolenine 18 both of which readily underwent methanolysis to give 6 in good yield.A mechanism for the acid catalyzed methanolysis of 3-chloro- and 3-bromoindolenines is proposed.
