29643-79-6Relevant articles and documents
Three-step assembly of 4-aminotetrahydropyran-2-ones from isoxazoline-2-oxides
Naumova,Mikhaylov,Khomutova,Novikov,Arkhipov,Korlyukov,Ioffe
, p. 12467 - 12475 (2014)
Tetrahydropyran-2-ones with a 4-amino function connected to a tertiary carbon atom-a widely naturally occurring fragment-are constructed by a three step protocol from easily available isoxazoline 2-oxides. In the first stage, the carbon skeleton of the target product is formed upon a C,C-coupling of a silyl ketene acetal with a nitronate function, under silyl triflate catalysis. The key step of the assembly consists of the oxidative cleavage of an endocyclic N-O bond of intermediate cyclic nitroso acetals with mCPBA, accompanied with lactone ring closure, and gives rise to β-nitro-δ-lactones in 63-85% yields. The latter are reduced with amalgamated aluminium, to furnish the target scaffold.
SUR LA REACTION DE REFORMATSKY. II-PREPARATION ET REACTIVITE DE L'ORGANOZINCIQUE ISSUS DU SEL BROMOZINCIQUE DE L'ACIDE γ-BROMOSENECIOIQUE.
Bellassoued, M.,Habbachi, F.,Caudemar, M.
, p. 1785 - 1792 (1987)
The condensation of benzaldehyde and cyclohexanone with the bromozinc salt derived from γ-bromosenecioic acid, in the presence of zinc, yield unsaturated hydroxyacids or lactones.The equilibration of the intermediary alcoxides is studied.
Synthesis of conjugated γ- and δ-lactones from aldehydes and ketones via a vinylation(allylation)-ring closing metathesis-oxidation sequence
Marco, J. Alberto,Carda, Miguel,Rodríguez, Santiago,Castillo, Encarnación,Kneeteman, María N.
, p. 4085 - 4101 (2007/10/03)
Nucleophilic C-vinylation and C-allylation of aldehydes and ketones followed by O-allylation of the obtained carbinols gave the corresponding allyl or homoallyl ethers, respectively. Ring-closing metathesis of these compounds afforded in many cases cyclic ethers (dihydrofurans and dihydropyrans, respectively) bearing disubstituted and trisubstituted C=C bonds. These were then subjected to allylic oxidation to yield conjugated γ- and δ-lactones. Reasons for the observed failures are presented and discussed.
A general synthesis of (2Z)-terpenoic acids
Cahard, Dominique,Mammeri, Malika,Poirier, Jean-Marie,Duhamel, Lucette
, p. 3619 - 3622 (2007/10/03)
A three-step synthesis of (2Z), (4E)-polyenic acids 6 is described. Condensation of aldehydes 1 with potassium prenal enolate led to dihydropyranols 3 which were oxidized into dihydropyrones 5, precursors of (2Z), (4E)-polyenic acids 6. The procedure was applied to a synthesis of 13- cis-retinoic acids from β-ionylidene acetaldehydes. (C) 2000 Elsevier Science Ltd.