Reaction of ketenylidenetriphenylphosphorane, Ph3PC=C=O, with water. Formation methyltriphenylphosphonium hydrogen carbonate

The reaction of the oxocumulene ylide ketenylidenetriphenylphosphorane, Ph3PC=C=O, 1, with an excess of water in THF yielded a white microcrystalline solid that was recognized as methyltriphenylphosphonium hydrogencarbonate, containing one molecule of crystallization water, [Ph3MeP]CO3H·H2O, 2. Compound 2 was characterized by IR, multinuclear NMR and ESI mass spectra. The chemical constitution was confirmed by an X-ray crystal analysis. On heating, compound 2 decomposes giving CO2, H2O, C6H6 and Ph2MePO.