Abstract
Addition of triethyl borate to disodium diselenide or to sodium decyl diselenolate
allows their reduction with sodium borohydride which otherwise does not take place.
Key words
selenium - reduction - sodium borohydride
References
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Disodium diselenide has been prepared, as already described as a brownish solution,
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[3a ]
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<A NAME="RG10705ST-5">5 </A> We have reported5a however, that n -butyllithium cleaves the Se-Se bond of lithium n -butyl diselenolate to produce 2 molar equiv of lithium n -butylselenolate. See:
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During the course of this work we observed that triethyl borate is produced besides
didecyl selenide on sequential reaction of elemental selenium, sodium borohydride,
ethanol and decyl bromide (Equation
[1 ]
, entry a). It has been distilled, in quantitative yield, from the crude mixture and
compared to an authentic sample purchased from the Sigma Aldrich Company. It was nevertheless
impossible to distill it out of the medium before addition of decyl bromide although
it was easy to remove the solvent (heating up to 120 °C) from the reaction mixture.