101602-07-7Relevant academic research and scientific papers
A concise approach to polysubstituted oxazoles from N-acyl-2-bromo enamides via a copper(i)/amino acid-catalyzed intramolecular C-O bond formation
Liu, Bingjie,Zhang, Yueteng,Huang, Gang,Zhang, Xinting,Niu, Pengfei,Wu, Jie,Yu, Wenquan,Chang, Junbiao
, p. 3912 - 3923 (2014/06/09)
A straightforward and efficient copper(i)/amino acid-catalyzed intramolecular Ullmann-type C-O coupling reaction has been developed. This protocol affords a facile methodology for the synthesis of a series of novel 2,4,5-substituted oxazoles from readily accessible N-acyl-2-bromo enamides under mild conditions. This journal is the Partner Organisations 2014.
Access to di- and trisubstituted oxazoles by NBS-mediated oxidative cyclisation of N-acyl amino acid derivatives
Bathula, Surendar Reddy,Reddy, Muktapuram Prathap,Viswanadham, K. K. Durga Rao,Sathyanarayana, Pochampalli,Reddy, Maddi Sridhar
, p. 4552 - 4557 (2013/07/26)
A remarkably simple method for the synthesis of di- and trisubstituted functionalised oxazoles under metal- and catalyst-free conditions is described. An iterative bromination and debromination of N-acylated amino acid derivatives with NBS as the sole rea
Synthesis and electrochemical behaviour of β-halodehydroamino acid derivatives
Ferreira, Paula M. T.,Monteiro,Pereira
experimental part, p. 499 - 513 (2010/11/04)
Several new β,β-dihalo and β-halo-β-substituted dehydroalanines and dehydrodipeptides were synthesized by reacting the corresponding dehydroamino acid derivative with a N-halosuccinimide or in the case of β,β-di-iododehydroalanines with iodine. The results obtained confirmed that the stereochemical outcome of the halogenation reaction with β-substituted dehydroamino acids depends on the substrate. Thus, an increase Z-stereoselectivity was found when the β-phenyldehydroalanines were used as substrates and when these compounds were N-protected with 4-tolylsulfonyl or with carbamates. From this study, it is also possible to conclude that when N-iodosuccinimide was used as reagent a much higher Z-stereoselectivity is found. The electrochemical behaviour of the halogenated dehydroamino acids was studied by cyclic voltammetry. The results show a shift in the reduction peak to higher potentials of the β-halogenated dehydroamino acids when compared with the corresponding non-halogenated derivatives. As expected, the β,β-dihalodehydroalanines exhibit higher peak potentials than β-halo-β-substituted dehydroalanines and the bromo derivatives have lower peak potentials when compared with the corresponding iododehydroamino acids. Controlled potential electrolysis of several β-halo-β-substituted dehydroamino acids afforded the corresponding dehalogenated dehydroamino acids as mixtures of their E and Z-isomers. In all cases, the major isomer isolated results from dehalogenation without isomerization. These new results show that electrochemical reduction constitutes a valuable method for the synthesis of the E-isomer of β-substituted dehydroalanines. Springer-Verlag 2010.
