Horner–Wadsworth–Emmons Reactions in THF: Effect of Hydroperoxide Species

Abstract

Horner–Wadsworth–Emmons (HWE) reactions routinely employ tetrahydrofuran (THF) as the reaction solvent. In this paper we show that THF adducts (derived from THF–hydroperoxide species) of HWE phosphonate ester compounds are formed under microwave irradiation (i.e., under pressure), or in the presence of a reductant [e.g., P(OEt)₃] in a conventionally heated reaction.

Key words

alkenes - phosphorus - peroxides - furan - reduction

• References and Notes

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Microwave-assisted Wittig reactions (ref. 2c. in THF) have been described, see:
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Due to health and safety restrictions we have been unable to run direct control reactions with THF-OOH. The isolation and purification of THF-OOH has been previously attempted, see:
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• 18b We do not recommend purification of THF-OOH by distillation – this could be extremely hazardous and dangerous!