Premium
Preparations and Reactions of 2‐Cyanoindole Derivatives
Author(s) -
Lin ChihDa,
Fang JimMin
Publication year - 1993
Publication title -
journal of the chinese chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.329
H-Index - 45
eISSN - 2192-6549
pISSN - 0009-4536
DOI - 10.1002/jccs.199300092
Subject(s) - chemistry , dimethyl acetylenedicarboxylate , cyclobutene , reagent , medicinal chemistry , electrophile , nucleophile , lithium (medication) , lithium diisopropylamide , sodium , organic chemistry , halogenation , cycloaddition , ion , ring (chemistry) , deprotonation , medicine , endocrinology , catalysis
2‐Cyano‐1‐phenylsulfonylindole (1a) and 2‐cyano‐1‐methylindole (1b) were prepared by chemical and electrolytic methods in modest yields. Nucleophiles such as sodium benzenethiolate, butyllithium and lithium dimethylcuprate attacked the sulfonyl group of 1a, whereas they attacked the cyano group of 1b. 1,3‐Dipolar cycloadditions of 1a and 1b with 2,4,6‐trimethylbenzonitrile oxide occurred at the cyano groups. Electrophilic reactions of 1b with N ‐bromosuccinimide, Vilsmeir reagent and acetyl chloride afforded the corresponding 3‐bromo‐, 3‐formyl‐ and 3‐acetylindole derivatives in modest or high yields, albeit less rapidly than the reactions of 1‐methylindole. Photochemical addition of dimethyl acetylenedicarboxylate to 1b was followed by cleavage of the cyclobutene intermediate to give dimethyl (2‐cyano‐1‐methylbenzazepine)‐3,4‐dicarboxylate.