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Names | |||
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Other names
1,2-Oxaphosphetane
1,3-Oxaphosphetane | |||
Identifiers | |||
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3D model (JSmol)
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ChemSpider |
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PubChem CID
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CompTox Dashboard (EPA)
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Properties | |||
C2H5OP | |||
Molar mass | 76.035 g·mol−1 | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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An oxaphosphetane is a molecule containing a four-membered ring with one phosphorus, one oxygen and two carbon atoms. In a 1,2-oxaphosphetane phosphorus is bonded directly to oxygen, whereas a 1,3-oxaphosphetane has the phosphorus and oxygen atoms at opposite corners.
1,2-Oxaphosphetanes are rarely isolated but are important intermediates in the Wittig reaction and related reactions such as the Seyferth–Gilbert homologation and the Horner–Wadsworth–Emmons reaction.[2] Edwin Vedejs's NMR studies first revealed the importance of oxaphosphetanes in the mechanism of the Wittig reaction in the 1970s.[3][4]
In 2005 the first isolation of 1,2-Oxaphosphetanes (typical Wittig intermediates) was reported.[5] One of the compounds was characterized by X-ray crystallography and NMR. Although relatively stable, thermal decomposition of these oxaphosphetanes gave a phosphonium salt, which slowly dissociated to the Wittig reaction starting materials, the carbonyl and olefin compounds.