“Dimethylphosphine oxide”的意思、由来-开放百科全书

词条

Dimethylphosphine oxide

释义

Preparation
Reactions
References

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| IUPACName =
| OtherNames = dimethylphosphinous acid tautomer
|Section1={{Chembox Identifiers
| CASNo = 7211-39-4
| PubChem = 81631
| ChemSpiderID = 10415346
| EC_number = 230-591-2
| SMILES = CP(=O)C
| StdInChI = 1S/C2H7OP/c1-4(2)3/h4H,1-2H3
| StdInChIKey = HGDIHUZVQPKSMO-UHFFFAOYSA-N}}
|Section2={{Chembox Properties
|C = 2|H = 7|O = 1|P = 1
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| Appearance = colorless liquid
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| BoilingPt = 65-67 ºC
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|Section3={{Chembox Hazards
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| GHSSignalWord = Warning
| HPhrases = {{H-phrases|302|315|319|335}}
| PPhrases = {{P-phrases|261|264|270|271|280|301+312|302+352|304+340|305+351+338|312|321|330|332+313|337+313|362|403+233|405|501}}
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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:^[1]

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:^[2]

(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

1. ^{{cite journal|author=Kleiner, H. J.|title=Herstellung und Umsetzungen von Dimethylphosphinoxid (Preparation and Reactions of Dimethylphosphine Oxide)|journal=Justus Liebigs Ann. Chem.|year=1974|pages=751-764|doi=10.1002/jlac.197419740507}}
2. ^{{cite journal|author=Hays, H. R.|title=Reaction of diethyl phosphonate with methyl and ethyl Grignard reagents|journal=J. Org. Chem.|year=1968|volume=33|pages=3690-3694|doi=10.1021/jo01274a003}}

1 : Organophosphine oxides

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