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Density functional study of conversions of 2,3-dimethyl-2,3-butanediol and 2,3-dimethyl-2,3-pentanediol in acid-catalyzed systems |
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| รหัสดีโอไอ | |
| Title | Density functional study of conversions of 2,3-dimethyl-2,3-butanediol and 2,3-dimethyl-2,3-pentanediol in acid-catalyzed systems |
| Creator | Tadtanu Shanyib |
| Contributor | Vithaya Ruangpornvisuti |
| Publisher | Chulalongkorn University |
| Publication Year | 2549 |
| Keyword | Catalysis, Ethanes, Diacetyl, Density functionals, Pinacol rearrangement |
| Abstract | Conversion reactions of 2,3-dimethyl-2,3-butanediol (DMBDOL) to 2,3-dimethyl-1,3-butadiene (DMBDENE) and 2,3-dimethyl-2,3-pentanediol (DMPDOL) to 2,3-dimethyl-1,3-pentadiene (DMPDENE) in acid-catalyzed system have been investigated using density functional theory method at B3LYP/6-31G(d) and B3LYP/6-311+G(d,p) levels of theory. Activation energies of conversion reaction of 2,3-dimethyl-2,3-butanediol (DMBDOL) and 2,3-dimethyl-2,3-butanediol with molecule of water in acid-catalyzed systems are 55.13(60.17) and 26.21(30.42) kcal/mol, respectively. The activation energy of conversion reaction of 2,3-dimethyl-2,3-pentanediol (DMPDOL) and 2,3-dimethyl-2,3-pentanediol with molecule of water in acid-catalyzed systems is 69.74(67.15) and 20.12(29.05) kcal/mol, respectively (method B3LYP/6-31G(d) is in the parenthesis). The activation energy of the conversion reaction of 2,3-dimethyl-2,3-butanediol and 2,3-dimethyl-2,3-pentanediol are decreased when the water molecule was added. The water molecule is sufficient to affect protonation, can acts as a base to remove the adjacent protons from intermediates. |
| URL Website | cuir.car.chula.ac.th |
