91640-35-6Relevant articles and documents
An efficient green protocol for the preparation of acetoacetamides and application of the methodology to a one-pot synthesis of Biginelli dihydropyrimidines. Expansion of dihydropyrimidine topological chemical space
Gama, Fernando H. S.,De Souza, Rodrigo O. M. A.,Garden, Simon J.
, p. 70915 - 70928 (2015/09/08)
The present study describes the preparation of N-aryl-(15) and N-alkyl-(17) acetoacetamides, in good to excellent yields, using both conventional and microwave heating, by reaction of amine derivatives (14 and 16) with 2,2,6-trimethyl-4H-1,3-dioxin-4-one (TMD, 12) in aqueous medium. The acetoacetamides were used to prepare novel Biginelli dihydropyrimidine derivatives. The introduction of the amino acid derivatives potentially allows for the exploration of new structural complexity and topologically diversifies the chemical space occupied by this versatile chemical scaffold.
Substituent Effects on the Product Distribution in Diazo Amide Photochemistry. Role of Ground-State Conformational Populations
Tomioka, Hideo,Kondo, Masato,Izawa, Yasuji
, p. 1090 - 1094 (2007/10/02)
Effects of substituents on the photochemical processes of several α-diazo amides (1a-f) have been studied .Irradiation of 1b in ethyl ether and acetone afforded, in addition to a β-lactam, the reaction products with the solvents, ie., EtOCH2CONMe2 and 1,3-dioxolane, respectively, whereas similar irradiation of 1a in these solvents gave only intramolecular reaction products, ie., β- and γ-lactams.Displacement of oneof the alkyl groups on the amide nitrogen with a Ph group markedly changed its photochemical processes.Thus irradiations of 1c and 1d in MeOH gave oxindole almost exclusively.Introduction of an acetyl group on the diazo carbon also caused a change in the product distributions.Photolysis of 1e in methanol gave, for exaple, the Wolff rearrangement (WR) product of Me migration and a β-lactam, whereas similar irradiation of 1f afforded WR product and oxindole.The results are interpreted as indicating that the β-lactam, the oxindole, and the WR product are derived from the excited singlet state of s-Z form of the diazo amide itself, whereas that of s-E form dissociates nitrogen to generate singlet carbene, and that populations of each conformers in the ground state are important in determining the photochemical processes of the α-diazo amide.
