title: The NH---FC dipole orientation effect for pendant exocyclic CH(2)F.
abstract: [structure: see text] DFT and MMFF force field calculations for 2 (R = H) predict that two conformers dominate in water (>/=95%) and both sustain a geometry in which the C-F and H-N dipoles align oppositely in a near-planar arrangement. The (1)H NMR spectra (D(2)O and DMSO-d(6)) and X-ray structure for 2 (R = SO(2)NHEt) confirm the predictions in all essentials. A novel single-conformer system is proposed.
authors.affiliation: Pharmacia Corporation, 4901 Searle Parkway/P-024, Skokie, Illinois 60077, USA.
authors.forename: David C
authors.initials: DC
authors.lastname: Lankin
authors.forename: Gary L
authors.initials: GL
authors.lastname: Grunewald
authors.forename: F Anthony
authors.initials: FA
authors.lastname: Romero
authors.forename: Ilkay Yildiz
authors.initials: IY
authors.lastname: Oren
authors.forename: James P
authors.initials: JP
authors.lastname: Snyder
mesh_terms: D018360:Crystallography, X-Ray; D005461:Fluorine / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009930:Organic Chemicals / Q000737:chemistry*
chemical_list: D009930:Organic Chemicals; D005461:Fluorine