A Computational Investigation of the Geometrical Structure and Protodeboronation of Boroglycine, H2N-CH2-B(OH)2
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- 作者：Joseph D. Larkin ; Krishna L. Bhat ; George D. Markham ; Bernard R. Brooks ; Jack H. Lai ; Charles W. Bock
- 刊名：Journal of Physical Chemistry A
- 出版年：2007
- 出版时间：July 19, 2007
- 年：2007
- 卷：111
- 期：28
- 页码：6489 - 6500
- 全文大小：256K
- 年卷期：v.111,no.28(July 19, 2007)
- ISSN：1520-5215
文摘
In this article the geometrical structure of the simple, achiral, 
-amino boronic acid boroglycine, H2N-CH2-B(OH)2, was investigated using density functional theory (DFT), second-order M
ller-Plesset (MP2)perturbation theory, and coupled cluster methodology with single- and double-excitations (CCSD); the effectsof an aqueous environment were incorporated into the results by using a few explicit water molecules and/orself-consistent reaction field (SCRF) calculations with the IEF polarizable continuum model (PCM). Neutralreaction mechanisms were investigated for the direct protodeboronation (hydrolysis) of boroglycine (H2O +H2N-CH2-B(OH)2 
B(OH)3 + H2N-CH3), for which 
e10001.gif"> was -21.9 kcal/mol at the MP2(FC)/aug-cc-pVDZ level, and for the 1,2-carbon-to-nitrogen shift of the -B(OH)2 moiety (H2N-CH2-B(OH)2 H3C-NH-B(OH)2), for which the corresponding value of e10002.gif"> was -18.2 kcal/mol. A boron-oxygen double-bonded intermediate was found to play an important role in the 1,2-rearrangement mechanism.
-amino boronic acid boroglycine, H2N-CH2-B(OH)2, was investigated using density functional theory (DFT), second-order Mller-Plesset (MP2)perturbation theory, and coupled cluster methodology with single- and double-excitations (CCSD); the effectsof an aqueous environment were incorporated into the results by using a few explicit water molecules and/orself-consistent reaction field (SCRF) calculations with the IEF polarizable continuum model (PCM). Neutralreaction mechanisms were investigated for the direct protodeboronation (hydrolysis) of boroglycine (H2O +H2N-CH2-B(OH)2 B(OH)3 + H2N-CH3), for which H3C-NH-B(OH)2), for which the corresponding value of