Unusual Transformations of Highly Unsaturated Trifluoromethanesulfonamide Derivatives

Oxidative condensation of N,N-bis(prop-2-yn-1-yl)trifluoromethanesulfonamide in DMSO involved only one ethynyl group, whereas in aqueous methanol 1,8-bis(trifluoromethanesulfonyl)-1,8-diazacyclotetradeca-3,5,10,12-tetrayne was obtained. N,N′-(Hexa-2,4-diyn-1,6-diyl)bis(trifluoromethanesulfonamide) in hexane solution was unexpectedly converted to diphenyldiacetylene, presumably, as a result of annulation of highly unsaturated carbon chains in the initial polyacetylene molecule and elimination of trifluoromethanesulfonamide and trifluoromethanesulfonamidomethyl residues.