Regio- and stereoselective Cu-catalyzed addition of the above hypervalent iodine reagent to alkynes and alkenes was achieved. In the presence of CuI, the reaction is suitable to perform trifluoromethyl-benzoyloxylation and trifluoromethyl-halogenation of alkenes and alkynes. Electron-donating substituents accelerate the process, and alkenes react faster than alkynes emphasizing the electrophilic character of the addition reaction.

Alkenes and Alkynes. -The reaction of the hypervalent iodine reagent (I) with alkynes proceeds with complete stereoselectivity. In some cases, the yield can be increased by applying a stoichiometric amount of the copper salt. Electron-donating substituents accelerate the reaction. The reaction with mono-and disubstituted alkenes affords the expected trifluoromethyl benzoates. Iodination or bromination takes place in the reaction of (X) with stoichiometric amounts of CuI or CuBr. -(JANSON, P. G.; GHONEIM, I.; ILCHENKO, N. O.; SZABO*, K. J.; Org. Lett. 14 (2012) 11, 2882-2885, http://dx.doi.org/10.1021/ol3011419 ; Dep. Org. Chem., Arrhenius Lab., Univ. Stockholm, S-106 91 Stockholm, Swed.; Eng.) -R. Steudel 40-065