A 'Click' Approach to the Synthesis of 3-[2-(1-Alkyltriazol-4-yl)ethyl]indoles

Copper-catalyzed cycloaddition of N-(tert-butoxycarbonyl)-3-(1-tosyl-3-butynyl)-1H-indole with various azides readily provides the corresponding (triazolylethyl)indoles. These derivatives can be regarded as indole-3-propionic acid mimics because of the electronic features of the triazole ring that are closely related to the amido group. The obtained (indolylethyl)triazoles can be further functionalized exploiting an elimination-addition reaction involving the tosyl group.