Reactions of cyanooxo-molybdates and -tungstates with picolinic acid, 2-pyridinecarboxaldehyde and 2,2′-pyridil: X-ray crystal structure of (PPh4)2[Mo(CN)4O(pic)] · 2.5H2O

The new salts of Mo(IV) and W(IV) with picolinic acid and 2-pyridinecarboxaldehyde were described and characterised. It was shown for the first time that bidentate ligand can coordinate to [W(CN)5O]3− and that OH− ligand in [Mo(CN)4O(OH)]3− can be exchanged. The reaction was found to be relatively slow and can be observed due to the fact that protonated organic ligand is unreactive at pH with predominant [Mo(CN)4O(H2O)]2− species.