A ‘click’ approach to the synthesis of 3-(1-alkyltriazolyl)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.