The NH---FC dipole orientation effect for pendant exocyclic CH(2)F.
[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.
Lankin
David C
DC
Pharmacia Corporation, 4901 Searle Parkway/P-024, Skokie, Illinois 60077, USA.
Grunewald
Gary L
GL
Romero
F Anthony
FA
Oren
Ilkay Yildiz
IY
Snyder
James P
JP
D018360:Crystallography, X-Ray; D005461:Fluorine / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009930:Organic Chemicals / Q000737:chemistry*
D009930:Organic Chemicals; D005461:Fluorine