Spectroscopic study of complex formation by methanol and phenyl isocyanate with bis(acetylacetonato) copper

It has been shown that the reaction of phenyl isocyanate with methanol in dioxane in the presence of bis(acetylacetonato) copper involves the formation of intermediate complexes. The isocyanate is coordinated to the copper ion of the catalyst, and the alcohol is joined to the oxygen of the chelate rings of bis(acetylacetonato) copper together and hydrogen bond. This brings the reacting molecules closer together and orients them relative to one another, thus facilitating their interaction. The phenylmethylurethan formed is also coordinated to the catalyst, and when it appears in the system, equilibrium is established between the complexes formed by the catalyst with the solvent, the isocyanate, and the urethan.