Isolation of N-Heterocyclic Carbene-Stabilized Phosphorus and Arsenic Mononitride

Phosphorus mononitride (PN) and arsenic mononitride (AsN) species supported by two different N-heterocyclic carbenes were prepared: The reaction of (IDipp)NSiMe₃] IDipp = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene] with PCl₃ or AsCl₃ afforded the dichlorides (IDipp)NECl₂] (E = P, As) and, after the addition of IMes IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene], the cationic chloro species (IDipp)NE(Cl)(IMes)]Cl (E = P, As), which were reduced with potassium graphite (KC₈) to yield the neutral compounds (IMes)PN(IDipp)] and (IMes)AsN(IDipp)], which exhibit the typical trans-bent geometry of dicarbene-dielement species in the solid state according to single-crystal X-ray diffraction.