Horner-Wadsworth-Emmons Reaction

Metalated phosphonates are more reactive than analogous phosphonium ylids (Wittig reagents). The HWE reaction is usually used when the nucleophilic carbon bears a strong anion stabilizing group (CO2Me, COMe, COH, CN, SO2R, SOR). These reagents are trans-selective if the substituents on phosphorus are simple alkoxy groups.

Intramolecular reactions have been successfully used to close large rings. The example below is a key step in the synthesis of Rhyzoxin D. Williams. D. R.; Werner, K. M.; Feng, B. Tetrahedron Lett. 1997, 38, 6825


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   Synthesis 2001, 349-57.

© Hans J. Reich

Fall 2004

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