The simultaneous in-situ generation of aldehydes and phosphorus ylides. A convenient multi-step one-pot olefination protocol

Li a-(dimethylamino)alkoxides resulting from the nucleophilic addn. of an organolithium reagent to DMF are basic enough to deprotonate alkyltriphenylphosphonium salts suspended in THF. The aldehydes, liberated by the spontaneous decompn. of the resulting a-amino alcs. (hemi-aminals), undergo a Wittig reaction with the simultaneously generated P ylides to afford olefins in excellent overall yields. This in situ method offers the unique advantage in its applicability to labile aldehydes which otherwise would become prey to (Z/E)-isomerization or self-condensation processes. [on SciFinder (R)]


Published in:
European Journal of Organic Chemistry, 12, 3263-3268
Year:
1999
Keywords:
Note:
CAN 132:22577 21-2 General Organic Chemistry Institut Chimie Organique,Univ. Lausanne,Lausanne,Switz. Journal 1434-193X written in English. 68-12-2 (DMF); 110-83-8 (Cyclohexene); 401-78-5 (3-Bromobenzotrifluoride); 588-72-7 (E-b-Bromostyrene); 590-13-6 (Z-1-Bromopropene); 591-50-4 (Iodobenzene); 1014-60-4 (1,3-Di-tert-butylbenzene); 1449-46-3 (Benzyltriphenylphosphonium bromide); 1530-33-2 (Isopropyltriphenylphosphonium bromide); 1779-51-7 (Butyltriphenylphosphonium bromide); 4762-26-9 (Hexyltriphenylphosphonium bromide); 5293-84-5 ((Chloromethyl)triphenylphosphonium chloride); 6228-47-3 (Propyltriphenylphosphonium bromide); 21406-61-1 (Pentyltriphenylphosphonium bromide); 35761-83-2 (Z-3-Iodo-2-buten-1-ol); 37428-50-5 (Z-3-Iodo-2-propen-1-ol); 57918-63-5 (Z-b-Iodostyrene); 62285-98-7; 96385-23-8 Role: RCT (Reactant), RACT (Reactant or reagent) (Wittig olefination with simultaneous in-situ generation of aldehydes and phosphorus ylides); 6130-97-8P; 119125-30-3P; 148802-00-0P; 151502-81-7P Role: RCT (Reactant), SPN (Synthetic preparation), PREP (Preparation), RACT (Reactant or reagent) (Wittig olefination with simultaneous in-situ generation of aldehydes and phosphorus ylides); 351-78-0P (b-Fluorostyrene); 2198-23-4P (4-Nonene); 3740-05-4P; 4911-56-2P (5,5-Dimethyl-1,3-hexadiyne); 19789-42-5P (3,5-Di-tert-butylstyrene); 28495-61-6P; 31915-94-3P; 39491-72-0P; 39491-73-1P; 92260-77-0P; 118304-54-4P; 119946-52-0P; 132313-14-5P; 251987-55-0P; 251987-59-4P Role: SPN (Synthetic preparation), PREP (Preparation) (Wittig olefination with simultaneous in-situ generation of aldehydes and phosphorus ylides)
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 Record created 2006-03-03, last modified 2018-01-27


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