carbon monoxide in deuterated toluene byproducts: 3-pentanone; Co-complex was dissolved in toluene-d8, soln. was filtered into NMR tube, soln. was degassed, tube was sealed under CO (3 atm, at 25°C); monitored by NMR;

carbon monoxide in THF-d8 (tetrahydrofuran-d8); benzene (CpCo(CO)(CH3))2 and (CpCo(CO)(CH3CH2))2 were placed in NMR tube, THF-d8 and benzene were distilled into the tube, tube was sealed under CO (3 atm, 25°C), tube was thawed at -78°C; monitored by NMR;

in tetrahydrofuran Co-complex was dissolved in THF, soln. was transferred to an IR cell; monitored by IR;