Modulating Jousting C-F-H-C Interactions with a Bit of Hydrogen Bonding

We have synthesized a series of molecules wherein very close C-F-H-C sigma-bond interactions, which we have termed jousting, can be perturbed through both red- and blue-shifted hydrogen bonding effects. These interactions were induced by the placement of various functional groups geminal to the H-C bond. Jousting interactions appear to be an admixture of F-H hydrogen bonding and C-H bond compression. The associated electronic effects from changes in the functional group at the X-position were also studied.