Search

Base-catalyzed Michael addition of nitroalkane to conjugated nitroalkene suffers serious practical difficulties due to the formation of oligomeric byproduct. Given its importance for synthesis of pharmacologically relevant organic compounds, a scalable synthesis of 1,3-dinitroalkane is developed by addition of nitroalkane to nitroalkene in aqueous phosphate buffer at pH 7.0 with no added traditional base catalyst. Key words: 1,3-dinitroalkanes, Michael addition, phosphate buffer, base free, diastereoselective. La reaction de Michael catalysee par une base pour effectuer l'addition d'un nitroalcane a un nitroalcene conjugue pose des difficultes pratiques majeures en raison de la formation de sous-produits oligomeriques. Etant donne son importance pour la synthese de composes possedant une activite pharmacologique, nous avons elabore une synthese de 1,3-dinitroalcanes adaptable a grande echelle qui procede par addition d'un nitroalcane a un nitroalcene dans un tampon aqueux de phosphate a pH 7,0, sans catalyseur basique. [Traduit par la Redaction] Mots-cles: 1,3-dinitroalkanes, addition de Michael, tampon phosphate, sans base, diastereoselective., Introduction In organic synthesis, methods for the development of carbon-carbon bond forming reactions are considered as the cornerstone of building complex molecular architechture. (1-5) Many of such C-C bond forming [...]

A catalytic amount (2 mol %) of phosphotungstic acid (PTA) is sufficient to synthesize homoallylic alcohol in excellent yields from aldehyde with allyltributylstannane upon grinding under solvent-free reaction conditions. Easy handling, very short reaction time, solvent-free reaction conditions, and aqueous workup free isolation protocol may make our method very useful for synthetic chemists. Key words: aldehyde, allyltributylstannane, homoallylic alcohol, phosphotungstic acid, grinding. Une quantite catalytique (2 mol %) d'acide phosphotungstique (APT) est suffisante pour effectuer la synthese d'alcools homoallyliques, avec d'excellents rendements, par broyage d'un aldehyde avec de l'allyltributylstannane dans des conditions reactionnelles sans solvant. La facilite de la manipulation, son temps de reaction tres court, les conditions reactionnelles sans solvant et le protocole d' extraction en milieu aqueux pourrait en faire une methode tres precieuse pour les chimistes de synthese. Mots-cles : aldehyde, allyltributylstannane, alcool homoallylique, acide phosphotungstique, broyage. [Traduit par la Redaction], Introduction In recent years, organic synthesis under solvent-free conditions has been considered to be one of the most important features for designing environmentally benign reaction protocols. (1,2) The solvent-free reactions [...]