Study of Conversion of Polymeric Organophosphorus Ylide Complexes of Mercury(II) Halides to Phenazine Complexes: X-Ray Crystal Structures and Spectral Characterizations

GRAPHICAL ABSTRACT

Abstract

The reaction of PPh₃ with BrCH₂C(O)PhNO₂ leads to a new phosphonium salt [Ph₃P‒CH₂C(O)PhNO₂]Br (1). Reaction of the salt 1 with an appropriate base gave the free ligand, Ph₃P˭C(H)C(O)PhNO₂ (2). The reactions of ligand 2 with mercury(II) halides form the C-coordinated polymeric complexes [(2)HgX₂]_n {X = Cl (3), Br (4), I (5)}. Reactions of benzo[a]quinoxalino[2,3-c]phenazine ligand (L) with complexes 3, 4, and 5 cause the removal of ylidic ligand and lead to the formation of a new set of mononuclear mercury halides complexes {[(L)HgCl₂] (6), [(L)HgBr₂] (7), and [(L)HgI₂] (8)} containing (L) as a bidentate ligand. The structures of 4 and 6 were confirmed by single-crystal X-ray analysis. The structure of the products were identified by IR, ¹H, and ³¹P NMR spectral data and elemental analysis.

Keywords:

• Mercury
• phosphorus ylide
• polymeric phosphorus complex
• N,N–chelating ligand
• phenazine complexes