No abstract

No abstract

No abstract

SummaryTreatment of readily prepared (Z)-6-benzyloxy-1,1,1,2-tetrafluoro-6-methyl-2-hepten-4-yne with 1.5 equiv of LHMDS in −78 °C for 1 h gave the corresponding trifluoromethylated diyne in an excellent yield. This diyne was found to be a good substrate for the carbocupration with various higher-ordered cyanocuprates to give the corresponding vinylcuprates in a highly regio- and stereoselective manner. The in situ generated vinylcuprates could react very smoothly with an excess amount of iodine, the vinyl iodides being obtained in high yields. Thus-obtained iodides underwent a very smooth Sonogashira cross-coupling reaction to afford various trans-enediynes in high yields.

Highly Stereoselective Approach to 3-Fluoroalkylated (E)-Hex-3-ene-1,5-diyne Derivatives via an Addition-Elimination Reaction. -Five 1-fluoroalkylated 1-fluoroenyne compounds of type (III) are prepared. Addition-elimination reactions of these compounds with various alkynyllithium compounds yield diyne derivatives of type (V)/(VI) with excellent E-selectivity. -(KONNO*, T.; KISHI, M.; ISHIHARA, T.; YAMADA, S.; J. Fluorine Chem. 156 (2013) 144-151, http://dx.doi.org/10.1016/j.jfluchem.2013.09.010 ; Dep. Chem. Mater. Technol., Kyoto Inst. Technol., Sakyo, Kyoto 606, Japan; Eng.) -M. Bohle 18-063