Double E─H Bond Activation of Ammonia and Water by Cyclic Gallaphosphene L(OCP)GaPGaL

Abstract

Abstract Cyclic gallaphosphene L(PCO)GaPGaL 1 (L = HC[C(Me)NAr] 2 ; Ar = 2,6‐ i ‐Pr 2 ‐C 6 H 3 ) selectively reacts with NH 3 and H 2 O at ambient temperature with twofold N─H and O─H bond activation and formation of compounds LGa(μ‐PH)(μ‐NHC(O)PH)GaL 2 and LGa(μ‐PH)(μ‐OC(O)PH)GaL 3 . Both nucleophilic P atoms of 1 are protonated in these reactions, while the electrophilic carbon atom of the bridging PCO unit binds to the remaining NH group / O atom. The formation of heterocycles 2 and 3 , which were characterized by heteronuclear NMR ( 1 H, 13 C{ 1 H}, 31 P{ 1 H}) and IR spectroscopy, elemental analysis, and single‐crystal X‐ray diffraction (sc‐XRD), is only possible due to a beneficial interplay between the polar Ga─P double bond and the electrophilic nature of the C center in the bridging PCO unit. The reaction mechanism and energetics of the NH 3 reaction was investigated in detail by quantum chemical calculations, which also highlight the importance of bimolecular reaction processes with the involvement of an additional NH 3 molecule.