AM1 study of acid-catalyzed hydrolysis of maleamic (4-amino-4-oxo-2-butenoic) acids
β Scribed by Toshiyuki Katagi
- Publisher
- John Wiley and Sons
- Year
- 1990
- Tongue
- English
- Weight
- 546 KB
- Volume
- 11
- Category
- Article
- ISSN
- 0192-8651
No coin nor oath required. For personal study only.
β¦ Synopsis
The acid-catalyzed hydrolysis mechanisms of maleamic (4-amino-4-0~0-2-butenoic) acids were studied using AM1 method. The reaction proceeded mainly in two steps: (1) nucleophilic attack of the undissociated carboxyl group on the adjacent aminocarbonyl carbon via a zwitterionic intermediate; and ( 2 ) the rate-determining proton transfer to form the zwitterionic tetrahedral intermediate. In each step, the hydration of water and hydronium ion molecules was important in stabilizing the polarized intermediates. The substituent effects at the amide moiety and the 2,3-positions of the maleamic acids were qualitatively estimated for each step.
π SIMILAR VOLUMES
## Abstract A kinetic study of the release of the drug (__E__)β4β(4βmetoxyphenyl)β4βoxoβ2βbutenoic acid (MEPBA) from a poly(acrylic acidβ__co__βmethacrylic acid) (PAAβ__co__βMA) hydrogel was performed. The isothermal kinetic curves of MEPBA release from the PAAβ__co__βMA hydrogel in bidistilled wat