Thermal Rearrangement of Tris(hydroxymethyl)phosphine

Original Article:
Syntheses and rearrangements of tris(hydroxymethyl)phosphine and tetrakis(hydroxymethyl)phosphonium salts

Dmitry V. Moiseev, et al.

Phosphorus, Sulfur, and Silicon and the Related Elements, 2020, 195(9), 687-712.

10.1080/10426507.2020.1764957

Water-soluble tris(hydroxymethyl)phosphine (THP) is one of the most readily available organophosphorus compounds. THP is of academic and industrial importance. For example, THP is an effective ligand for the preparation of water-soluble metal complexes, can be used to remove metal catalysts from organic phases after synthesis, and is recognized as an effective cross-linking agent in biochemistry. THP is also an effective precursor for the synthesis of other hydroxymethyl and aminomethyl-phosphorus derivatives, some of which, such as tris(hydroxymethyl)phosphine oxide (THPO) and 1,3,5-triaza-7-phosphaadamantane, are also of academic and industrial importance.

In this article a series of thermal rearrangement reactions of THP are reviewed, to name a few:

(1) Being heated in an organic solvent at > 125 °C, THP converts into bis(hydroxymethyl)methylphosphine oxide (BHMPO) in excellent yields.

(2) Heating a mixture of THP and CH₂O at 75-80 °C forms the condensation product that on being heated above 150 °C under reduced pressure rearranges into 5-methyl-5-oxo-1,3,5-dioxaphosphinane.

(3) Refluxing THP in AcOH gives a mixture of phosphorus compounds, whereas hydrolysis of THPC with p-toluenesulfonic acid in glacial AcOH for 6 h at reflux gives just small amounts of BHMPO (8%) and CH₃P(O)(CH₂OH)( CH₂OAc) (2%).

Chemicals Related in the Paper:

Catalog Number	Product Name	CAS Number
ACM2767808	Tris(hydroxymethyl)phosphine	2767-80-8