• Source: Dimethylphosphine oxide

Dimethylphosphine oxide is an organophosphorus compound with the formula (CH3)2P(O)H. It is a colorless liquid that soluble in polar organic solvents. It exists as the phosphine oxide, not the hydroxy tautomer. A related compound is diphenylphosphine oxide. Both are sometimes called secondary phosphine oxides.




Preparation


The compound arises by the hydrolysis of chlorodimethylphosphine:

Me2PCl + H2O → Me2P(O)H + HCl
Methanol, but not ethanol, can also be used in place of water, the co-product being methyl chloride.
Since chlorodimethylphosphine is dangerous to handle, alternative routes to dimethylphosphine oxide have been developed. A popular method starts with diethylphosphite, according to the following idealized equations:

(C2H5O)2P(O)H + 3 CH3MgBr → (CH3)2P(O)MgBr + 2 MgBr(OC2H5) + CH4
(CH3)2P(O)MgBr + H2O → (CH3)2P(O)H + 2 MgBr(OH)




Reactions


Chlorination gives dimethylphosphoryl chloride. It undergoes hydroxymethylation with formaldehyde.

Me2P(O)H + CH2O → Me2P(O)CH2OH
Many aldehydes effect a similar reaction.




References

Kata Kunci Pencarian:

• Dimethylphosphine oxide
• Transition metal complexes of phosphine oxides
• Diethylphosphite
• Proton affinity
• Phosphanide
• List of gases
• Tetramethyldiborane