Synthesis and molecular structures of mercury(II) complexes of carbamoylmethylphosphoryl ligands

GRAPHICAL ABSTRACT

ABSTRACT

The reactions of carbamoylmethylphosphonates (CMP) and carbamoylmethylphosphine oxides (CMPO) with mercuric nitrate typically result in deprotonation of the methylene carbon atom spanning the phosphoryl and the amide carbonyl groups of the bifunctional ligand with concomitant formation of [Hg(L)](NO₃) compounds containing a stable mercury-carbon σ bond. The resulting organometallic compounds form dimers [Hg(L)(NO₃)]₂ via bidentate interactions between the phosphoryl oxygen atom and carbonyl oxygen atom in one [Hg(L)]⁺ unit and the Hg(II) ion in the second [Hg(L)]⁺ unit. Additional examples of this general reactivity/structure pattern are reported herein. In contrast, in Hg(II) complexes of two CMPO derivatives, in which the amide N-atom is functionalized with a 2-methylpyridine group, the trifunctional phosphine oxides are observed to behave as neutral ligands forming complexes (L′)Hg (NO₃)₂.

Keywords:

• Carbamoylmethylphosphonate
• Carbamoylmethylphosphinite
• Carbamoylmethylphosphine oxide
• mercury(II) complexes
• X-ray crystal structures

Funding

This material is based upon the work supported by the US Department of Energy (DoE), Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences and Biosciences Office, under Award Number DE-FG02–03ER15419 (RTP). In addition, funds from the US National Science Foundation assisted the purchase of the X-ray diffractometer (CHE-0443580) and NMR spectrometers (CHE-0840523 and 0946690).