766-39-2Relevant articles and documents
Mechanism of the decarboxylative dimerization of maleic anhydride under the influence of 2-aminopyridine
Baumann,Bosshard,Breitenstein,et al.
, p. 1897 - 1905 (1984)
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Baumann,Bosshard
, p. 2751 (1978)
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Synthesis and pH-dependent hydrolysis profiles of mono- and dialkyl substituted maleamic acids
Su, Shan,Du, Fu-Sheng,Li, Zi-Chen
supporting information, p. 8384 - 8392 (2017/10/19)
Maleamic acid derivatives as weakly acid-sensitive linkers or caging groups have been used widely in smart delivery systems. Here we report on the controlled synthetic methods to mono- and dialkyl substituted maleamic acids and their pH-dependent hydrolysis behaviors. Firstly, we studied the reaction between n-butylamine and citraconic anhydride, and found that the ratio of the two n-butyl citraconamic acid isomers (α and β) could be finely tuned by controlling the reaction temperature and time. Secondly, we investigated the effects of solvent, basic catalyst, and temperature on the reaction of n-butylamine with 2,3-dimethylmaleic anhydride, and optimized the reaction conditions to efficiently synthesize the dimethylmaleamic acids. Finally, we compared the pH-dependent hydrolysis profiles of four OEG-NH2 derived water-soluble maleamic acid derivatives. The results reveal that the number, structure, and position of the substituents on the cis-double bond exhibit a significant effect on the pH-related hydrolysis kinetics and selectivity of the maleamic acid derivatives. Interestingly, for the mono-substituted citraconamic acids (α-/β-isomer), we found that their hydrolyses are accompanied by the isomerization between the two isomers.
Preparation of the maleic anhydride nucleus from dichloro γ-lactams: Focus on the role of the N-substituent in the functional rearrangement and in the hydrolytic steps
Ghelfi, Franco,Pattarozzi, Mariella,Roncaglia, Fabrizio,Parsons, Andrew F.,Felluga, Fulvia,Pagnoni, Ugo M.,Valentin, Ennio,Mucci, Adele,Bellesia, Franco
experimental part, p. 3131 - 3141 (2009/04/06)
The preparation of the 3,4-dialkyl-substituted maleic anhydride nucleus, through the functional rearrangement of dichloro γ-lactams, allowed the comparison of various N-substituents in the functional rearrangement step. The 2-pyridyl group proved to be the most appropriate N-substituent for the hydrolysis of the 5-methoxy-1,5-dihydro-2H-pyrrol-2-one intermediate into the 5-hydroxy adduct, and for the hydrolysis of the maleimide nucleus into the maleic anhydride. The oxidation of the 5-hydroxy-1,5-dihydro-2H-pyrrol-2-one into the corresponding maleimide was achieved with manganese(IV) oxide. Georg Thieme Verlag Stuttgart.