Geometrical and Ground State Electronic Structures of Nitrosylcobalt Complexes [(RNCHCHNR)Co(NO)(CO)] (R = Isopropyl, 2,6‐Diisopropylphenyl or p‐Tolyl) from Experiment and DFT‐Calculations

The new complexes (RN=CH‐CH=NR)Co(NO)(CO), R = isopropyl ( 1 ), 2,6‐diisopropylphenyl ( 2 ) and p‐tolyl ( 3 ), were synthesized and spectroscopically characterized. Compounds 1 and 2 could be crystallized for X‐ray structure analysis, CO/NO disorder was observed for 1 . The results indicate a negligible amount of charge transfer from the Co(NO)(CO) moiety to the 1, 4‐diazabutadiene acceptor ligands in the ground state, in agreement with DFT calculations on 1 and as similarly reported for related 1, 4‐diaza‐1, 3‐butadiene complexes of Ni(CO)₂ and Fe(NO)₂.