Generation of cycloalkynes through deprotonation of cyclic enol triflates with magnesium bisamides.

Deprotonative generation of cyclohexynes, cycloheptynes, and cyclooctynes was achieved by controlling the reactivities of transient anionic species from the corresponding enol triflates with magnesium bis(2,2,6,6-tetramethylpiperidide) as a base. The starting enol triflates are readily obtained through triflation of the corresponding ketones, allowing direct access to the cycloalkynes.