Tris(dimethylamino)phosphine explained

Tris(dimethylamino)phosphine is an organophosphorus compound with the formula P(NMe₂)₃ (Me = methyl). It is a colorless oil at room temperature, and is one of the most common aminophosphines. Its structure has been determined by X-ray crystallography.^[1]

Tris(dimethylamino)phosphine acts as a base. It reacts with oxygen to give hexamethylphosphoramide, O=P(NMe₂)₃, and with sulfur to give the corresponding compound hexamethylthiophosphoramide, S=P(NMe₂)₃. It can also act as a ligand, forming complexes with a variety of metal centers.^[2] Its steric and electronic properties are similar to those of triisopropylphosphine.^[3]

Because of its affinity for sulfur, tris(dimethylamino)phosphine is also effective as a desulfurization agent, e.g., in the conversion of dibenzyl disulfide into dibenzyl sulfide:^[4]

PhCH₂SSCH₂Ph + P(NMe₂)₃ → S=P(NMe₂)₃ + PhCH₂SCH₂Ph (Ph = phenyl)

References

1. 10.1021/ja9621861. Low Symmetry in P(NR₂)₃ Skeletons and Related Fragments: An Inherent Phenomenon. Journal of the American Chemical Society. 118. 50. 12673–12682. 1996. Mitzel. Norbert W.. Smart. Bruce A.. Dreihäupl. Karl-Heinz. Rankin. David W. H.. Schmidbaur. Hubert.
2. 10.1021/ic50009a014. Complexes of Trivalent Phosphorus Derivatives. II. Metal Carbonyl Complexes of Tris(dimethylamino)-phosphine. Inorganic Chemistry. 2. 5. 936–944. 1963. King. R. B..
3. Tolman . C. A. . Steric effects of phosphorus ligands in organometallic chemistry and homogeneous catalysis . . 77 . 3 . 313–348 . 1977 . 10.1021/cr60307a002.
4. Sulfide Synthesis: Benzyl Sulfide. David N. . Harpp. Roger A.. Smith. Org. Synth.. 1978. 58. 138. 10.15227/orgsyn.058.0138.