Enantioselective chemisorption on model chirally modified surfaces: 2-Butanol on r-(1-naphthyl)ethylamine/Pd(111)
Document Type
Article
Publication Date
8-6-2009
Abstract
The enantioselective adsorption of propylene oxide and 2-butanol is explored on α-(1-naphthyl)-ethylamine (NEA) covered Pd(111) using temperature-programmed desorption (TPD), reflection-absorption infrared spectroscopy (RAIRS), and scanning tunneling microscopy (STM). The saturation coverage of NEA is ∼0.1 monolayers (ML), and it thermally decomposes to desorb hydrogen and HCN. 2-Butanol adsorbs enantioselectively on NEA-modified Pd(111), while propylene oxide does not, emphasizing the importance of hydrogen-bonding interactions. An enantioselectivity ratio, ER, of ∼2 (corresponding to an ee of ∼33%) is found at an NEA coverage of ∼0.055 ML, where 2-butanol adsorbs on the Pd(111) substrate. A second regime is found in which 2-butanol adsorbs on an NEA-covered surface with a maximum ER ∼ 1.8 (corresponding to an ee of ∼29%). This interaction appears to cause the NH2 group to reorient to facilitate hydrogen bonding interactions between 2-butanol and the amine group, and the heat of adsorption of ∼35 kJ/mol is typical of - OH..."NH2 hydrogen bond strengths. © 2009 American Chemical Society.
Publication Title
Journal of Physical Chemistry C
Recommended Citation
Burkholder, L.,
Stacchiola, D.,
Boscoboinik, J.,
&
Tysoe, W.
(2009).
Enantioselective chemisorption on model chirally modified surfaces: 2-Butanol on r-(1-naphthyl)ethylamine/Pd(111).
Journal of Physical Chemistry C,
113(31), 13877-13885.
http://doi.org/10.1021/jp903793n
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p/8133