Highly stereocontrolled synthesis of trans-enediynes via carbocupration of fluoroalkylated diynes
نویسندگان
چکیده
Treatment 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.
منابع مشابه
A phosphine-mediated stereocontrolled synthesis of Z-enediynes by a vicinal dialkynylation of ethynylphosphonium salts.
Z-Enediynes are prepared by a vicinal dialkynylation of triaryl(arylethynyl)phosphonium cations. The method, which proceeds under mild transition metal-free conditions, can be conducted on multigram scale as a one-pot, phosphine-mediated synthetic cycle giving enediyne products with excellent control of configuration.
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