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Please login to access the full content or check if you have access via Variation 7: Thermolytic Elimination from Alkyl Selenoxides

DOI: 10.1055/sos-SD-047-00322

Kostikov, R. R.; Khlebnikov, A. F.; Sokolov, V. V.Science of Synthesis, (201047826.

Alkyl phenyl selenoxides 91 upon heating undergo syn elimination to give alkenes (Scheme 36).[‌195‌] This has two principal advantages over the analogous elimination from sulfoxides: first, the reaction occurs at temperatures approximately 100°C lower and, second, the oxidation of selenides to selenoxides can be carried out with inexpensive oxidizing agents such as hydrogen peroxide, peracetic acid, or tert-butyl hydroperoxide. Substituent effects and stereochemistry are similar to those observed for sulfoxide eliminations, including faster rates for compounds forming conjugated alkenes (dienes, styrenes, enones) and aryl selenoxides bearing electron-withdrawing substituents. The formation of cyclohexene from cyclohexyl phenyl selenoxide proceeds more slowly than that of cyclopentene from cyclopentyl phenyl selenoxide.[‌196‌] The preparation of (R)-3-methylnon-1-ene (92) is typical for that of alkenes obtained by thermolytic elimination from alkyl selenoxides.[‌197‌]

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