Origin of Stereoselectivity of the Photoinduced Asymmetric Phase-Transfer-Catalyzed Perfluoroalkylation of β-Ketoesters.

The sources of asymmetric induction in the photoinduced phase-transfer-catalytic perfluoroalkylation of β-ketoesters were interpreted by density functional theory calculations. The calculations indicated that multiple hydrogen-bonding interactions mode rather than π-π stacking interactions model better described the transition structure of the reaction. The quantitative estimation of these noncovalent interactions within the key transition states identified that the O-H···O and specific C-H···O hydrogen bonds play key roles for the stereocontrol.