On the Nature of C-H⋅⋅⋅F-C Interactions in Hindered CF3-C(sp3) Bond Rotations

Journal article, 2011

In cinchona alkaloid-based scaffolds, hindered CF3 rotations have been observed. The variation in barrier heights for the CF3 rotations is controlled by the corresponding entropic changes when the substituents are changed from an allyl to a bulky 9-methylanthracenyl group. Quantum chemical and experimental studies have shown that the noncovalent C3′[BOND]H1⋅⋅⋅F[BOND]C interactions in the studied cases possess a weak hydrogen bonding-like