[reaction: see text] Ring-closing metathesis (RCM) of vinyl fluoride-containing dienes in the presence of ruthenium alkylidene carbene complex 11 proceeded efficiently to give six- and seven-membered cyclic vinyl fluorides. The RCM reaction was used to prepare amine- and sulfamide-linked cyclo-olefins, as well as carbocyclic systems, from a simple commercial fluoro-olefin.

Ring-closing metathesis (RCM) of sulfamide-linked enynes 7, 11 and 12 containing disubstituted alkynes afforded a series of novel 7-membered cyclic sulfamides 13−15 in good yield. Substrates 5, 9 and 10 containing mono-substituted alkynes gave either simple RCM products 18a−c or those arising from combinations of enyne RCM and olefin cross metathesis 16/17a−c depending on the reaction conditions. Not-

No abstract

Grubbs II catalyst mediated ring-closing metathesis (RCM) of mono-brominated dienes is reported to proceed in moderate to good yields (40–80%) where the linking chain contains five atoms, leading to carbocyclic and heterocyclic 7-membered bromo-olefins. Notably, RCM to form 5-, 6- or 8-membered bromo-olefins was unsuccessful, with the exception of one example where RCM afforded diethyl 3-bromocyclohex-3-ene-1,1-dicarboxylate. In this case a bromomethyl-substituted cyclohexene was obtained as a byproduct. The utility of selected bromo-olefin RCM products was demonstrated through their participation in Suzuki-Miyaura reactions. Vinyl halide exchange (BrCl) was noted as a side reaction under RCM conditions.