Carbon dioxide fixation by Co(salophen)

The study described in this article is concerned with the reaction of Co(salophen)Na [salophen = Bis(salicylaldehyde)phenylenediamine] [1] with carbon dioxide in alcoholic solution of sodium borohydride. The reduction performed with NaBH4 to produce cobalt(I) as nucleophile and sodium cation for bifunctional fixation of CO2. The pale brown product obtained from the reaction of reduced Co(salophen) and CO2 in alcoholic solution found to be unstable in solution and in the solid form and could not be fully characterized. This is a common feature of many metal-CO2 complexes reported in literature.[2] By comparing the behavior and nature of this product with similar complexes reported in literature and the data obtained from IR spectrum, Atomic absorption spectroscopy and flame photometry, the main product of the reaction between reduced Co(salophen) and CO2 in alcoholic solution may be formulated as [Co(salophenH2)CO2Na].