- Syntheses d'alcools allyliques et alleniques fonctionnels a partir de composes carbonyles α-phenylselenies
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The functionalized allylic selenides 6, 7, 8, 10 and 11 were prepared from phenylselenoaldehydes and ketones 1, and phenylselenopyruvates 2 using the Wittig or the Horner reaction. 2,3-Sigmatropic rearrangement of the corresponding selenoxides leads to the functional allylic alcohols 15, 16 and 17 and to the conjugated enals 18, 19 and 20.A method for the conversion of an aldehyde into the enal with an additional carbon is described.The functional 3-phenylselenobutadienes 23, 24 and 25 were also obtained from α-phenylselenoenals 21 in the same manner.An oxidation-rearrangement reaction appears to be a convenient way to prepare the functional or substitued allenic alcohols 26 and 28.The ethyl 2-hydroxy pent-3,4-dienoate 26c has been cyclized by benzeneselenenyl bromide into the ethyl 2,5-dihydrofurancarboxylate 29.
- Lerouge, Patrice,Paulmier, Claude
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p. 1225 - 1229
(2007/10/02)
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- PROPRIETES DES α-PHENYLSELENOALDEHYDES REACTIONS DE WITTIG CONDUISANT A DES α-HYDROXYESTERS ET CETONES β,γ-ETHYLENIQUES ET A DES ALDEHYDES α,β-ETHYLENIQUES
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Wittig and Wittig-Horner reactions with α-phenylselenoaldehydes lead to allylic selenides.The corresponding selenoxides undergo 2,3-sigmatropic rearrangement providing a route to α-hydroxy β,γ-ethylenic esters and ketones in good yields.In a some way, we prepare, also enals with an additional carbon.
- Lerouge, Patrice,Paulmier, Claude
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p. 1983 - 1986
(2007/10/02)
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