in tetrahydrofuran under inert gas; excess of Li-compound added to a stirred soln. at -78°C; poured into a separatory funnel (satd. NH4Cl soln.), org. layer dried (K2CO3), filtered, distilled; elem. anal.;

hydrogenchloride; potassium carbonate; bis(1,5-cyclooctadiene)nickel (0) in toluene (N2 or Ar); aq. HCl added to a soln. of Sn compd. in THF, stirred at room temp. for 6.5 h, treated with solid K2CO3, evapd., a soln. of Ni complex in toluene and 1,2-heptadiene added, stirred at 50°C for 3 h; filtered, concd., chromd. (preparative GPC);