Copper-CatalyzedCross-Coupling of Bicyclobutaneswith Triftosylhydrazone Leading to Skipped Dienes

Here, we report a protocol for the synthesis of skipped dienes through the cross-coupling of bicyclo[1.1.0]­butanes with trifluoromethyl triftosylhydrazones. The reaction is run using Tp^Br3Cu­(NCMe) as a catalyst to give access to a library of trifluoromethylated skipped dienes (32 examples, ≤98% yield) with excellent <i>E</i>/<i>Z</i> selectivity under mild and operationally safe conditions. The presented methods proved to be compatible with various functionalized bicyclo[1.1.0]­butanes and triftosylhydrazones.