Phosphorylation of Isocyanates and Aldehydes Mediated by Multifunctional N-Phosphine Oxide-substituted Imidazolylidenes

The direct syntheses of imidic-phosphinic mixed anhydrides and phosphinates were accomplished via phosphorylation of isocyanates or aldehydes with N-phosphine oxide-substituted imidazolylidenes (PoxIms) that are equipped with both nucleophilic carbene and electrophilic phosphorus moieties. In addition, the catalytic cyclotrimerization of phenyl isocyanate took place by employing a PoxIm having bis-N-phosphine oxide groups. The results presented in the current study demonstrate that judiciously designed multifunctional carbenes represent a promising potential for the phosphorylation of heterocumulenes and carbonyl compounds.