G. Szőllősi et al. / Catalysis Communications 32 (2013) 81–85
85
3.5. Interpretation of the results
Acknowledgment
Based on the experimental data presented in the manuscript – in
particular results from Subsections 3.3 and 3.4 – as well as the exper-
imental observations and quantum chemical computations published
in the literature, it seems justified to assume that enantioselection in
the Orito reaction cannot be interpreted via a single generalizable IC;
it may rather be the simultaneous presence of different types of inter-
actions dependent on a number of factors (modifier, substrate, and
solvent) that determines the sense of enantioselection. The following
interactions may be supposed to operate on the surface of Pt:
N\H—O_C, N\H—O, N–-H\O, O\H—O_C, C2\H—O, C8\H—O,
C5′\H—O_C, C6′\H—O_C, C5′\H—O, C6′\H—O, N\H—F, and
C\H—F.
Financial support by the Hungarian National Science Foundation
(OTKA Grant K 72065) is highly appreciated.
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Based on the above at the present stage of the research the role of
interactions other than N\H\O in enantioselection cannot be ex-
cluded. For example, in the enantioselective hydrogenations of KPL
on Pt–PhOCD and Pt–β-ICN catalysts, processes accompanied by re-
versal of the ee, the simultaneous presence and competition of inter-
actions of different strengths may regulate enantioselection (varied
multiple bonding model). Results of not yet attempted ATR-IR mea-
surements on the hydrogenation of KPL on Pt–PhOCD and Pt–β-ICN
catalysts are expected to contribute with significant new information
that will promote a deeper understanding of the stereochemistry of
the Orito reaction.