Inhibition of stannane-mediated radical rearrangements by a recoverable, minimally fluorous selenol

[GRAPHICS] The preparation of a minimally fluorous diaryl diselenide is described. It is demonstrated that this diselenide, reduced in situ to the corresponding selenol, may be used in conjunction with stannanes to prevent a number of radical rearrangements. A 1 M solution of this selenol used in admixture with Breslow's water-soluble stannane can be used to significantly inhibit a cyclopropylcarbinyl ring opening. The combination of the fluorous selenol and the polar stannane permits recovery of the selenol by continuous fluorous extraction and isolation of a stannane-free hydrocarbon product.