in tetrahydrofuran soln. of Mg compd. in THF was added dropwise to stirred cold suspn. of Co complex in THF under N2; stirred for 2 h; refluxed for 0.5 h; quenched with cold aq. HCl; filtered; petroleum ether added; filtered; residue combined; washed (EtOH, petroleum ether, H2O); dried (vac., P2O5); chromd. (silica gel, 20percent EtOAc/CHCl3); elem. anal.;

in acetonitrile Irradiation (UV/VIS); mixt. of Co complex and enyne in acetonitrile, which was deaerated in ultrasonic bath with bubbling argon, was refluxed for 19 h under argon; condensed in vac.; residue was pass through column of Florisil (CH2Cl2);eluate was subjected to TLC sepn. (hexane-ethyl acetate, 10/1);

in acetonitrile Irradiation (UV/VIS); mixt. of Co complex and enyne in acetonitrile, which was deaerated in ultrasonic bath with bubbling argon, was refluxed for 18 h under argon; condensed in vac.; residue was pass through column of Florisil (CH2Cl2);eluate was subjected to TLC sepn. (hexane-ethyl acetate, 10/1);

in acetonitrile Irradiation (UV/VIS); mixt. of Co complex and enyne in acetonitrile, which was deaerated in ultrasonic bath with bubbling argon, was refluxed for 22 h under argon; condensed in vac.; residue was pass through column of Florisil (CH2Cl2);eluate was subjected to TLC sepn. (hexane-ethyl acetate, 10/1);

in acetonitrile Irradiation (UV/VIS); mixt. of Co complex and enyne in acetonitrile, which was deaerated in ultrasonic bath with bubbling argon, was refluxed for 17 h under argon; condensed in vac.; residue was pass through column of Florisil (CH2Cl2);eluate was subjected to TLC sepn. (hexane-ethyl acetate, 10/1);

in acetonitrile byproducts: C6H5I; Electrolysis; Ar; electrolysis of a soln. of Co complex and an excess of diphenyliodonium salt in anhyd. acetonitrile with n-C4H9NBF4 (0.05 mol/L) at -0.8 V at 20°C till the current is 10-15percent of the initital value; not isolated, detected by cyclic voltammetry;