Dienyl triflones

Alkenyl and dienyl triflones also insert into unactivated C-H bonds. 

The Stille coupling between aryl halides and bis(tributylstannyl)ethyne furnishes symmetrical tolanes. Dienyl triflones are available in three steps from l-alkynes, with the reaction sequence terminated by a Stille coupling. 

Xiang, J. and Fuchs, P. L. 1996. AUcenylation of C-H bonds via reaction with vinyl and dienyl triflones. Stereospecific synthesis of trisubstituted vinyl triflones via organocopper addition to acetylenic triflones. J. Am. Chem. Soc. 118 11986-11987. 

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