TY - JOUR AU - Bürgi, T. AU - Atamny, F. AU - Knop-Gericke, A. AU - Hävecker, M. AU - Schedel-Niedrig, T. AU - Schlögl, R. AU - Baiker, A. TI - Adsorption mode of ethyl pyruvate on platinum: An in situ XANES study PY - 2000 JF - Catalysis Letters JA - Catal. Lett. SN - 1011-372X VL - 66 IS - 3 SP - 109 EP - 112 L1 - http://www.springerlink.com/content/p383211831k88002/fulltext.pdf L2 - http://www.springerlink.com/content/p383211831k88002/fulltext.html L3 - http://www.springerlink.com/content/p383211831k88002/ M3 - 10.1023/A:1019047622959 UR - http://dx.doi.org/10.1023/A:1019047622959 KW - ethyl pyruvate KW - in situ XANES KW - enantioselective hydrogenation KW - platinum N2 - The adsorption of ethyl pyruvate on Pt(111) has been studied by in situ XANES measurements in the presence and absence of hydrogen. Depending on the hydrogen and ethyl pyruvate pressure, the C and O K‐edge spectra exhibit distinctly different angular dependence. Without hydrogen ethyl pyruvate is oriented preferentially perpendicular to the surface, indicating bonding via the O lone pairs. In the presence of hydrogen the mean orientation is more tilted towards the surface. Likely, ethyl pyruvate also interacts with Pt via its π system under these conditions. The observed angle‐dependent shift of the energy of the π* and σ* resonances indicates the coexistence of differently adsorbed ethyl pyruvate species. The experimental findings demonstrate the importance of the in situ approach for unraveling the adsorption mode of ethyl pyruvate in the enantioselective hydrogenation over cinchona‐alkaloid‐modified Pt. ID - 1157 ER -