M. Nakagawa*, T. Hino
1970
Citations
0
Influential Citations
19
Citations
Journal
Tetrahedron
Abstract
Abstract 2-Ethoxy-3-methyl-(7) and 2-ethoxy-1,3-dimethyl-(11) and 2-ethoxy-1,3,3-trimethyl-3 H -indole (14) hydrofluoroborates have been prepared by a reaction of the corresponding oxindoles with Meerwein reagent. 2-Ethoxy-3-methylindole obtained upon basification of its fluororic acid salt (17) is unstable and autoxidizes to 2-ethoxy-3-methyl-3-hydroxy-3 H -indole (9). 2-Ethylthioindole and 2-ethylthio-3-methyl-indole (18) have been prepared; 18 is stable enough to be isolated, but undergoes similar autoxidation in hexane or cyclohexane to afford quantitatively the hydroxy derivatives 19 and the sulfoxide 20 in 1:1 ratio. The acid catalyzed hydrolysis of 2-ethoxy and 2-ethylthioindoles and nucleophilic displacement reactions of these compounds with amines have been studied.