Synthetic Radical Reactions Using Dibutylchlorogermane and ­Dibutylethoxygermane as Radical Mediators

Abstract

In the presence of Et₃B as radical initiator, dibutylchlorogermane (1a) and dibutylethoxygermane (1b) reacted with bromo- and iodoalkanes at room temperature to give the corresponding alkanes in high yields. Hydrogermane 1a was more reactive than 1b. However, 1b worked as a better radical mediator in intermolecular radical addition of haloalkanes to electron-deficient alkenes.

Key words

addition reactions - halides - organometallic reagents - radical reactions - reductions

References

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10

The use of Bu₂SnH₂ as reducing agent was also attempted for the reduction of 2a. The Et₃B-initiated reaction with Bu₂SnH₂ (1.2 equiv) for 24 h gave 3a in 34% yield with recovery of 2a (ca. 50%).