title: The observed and calculated 1H and 13C chemical shifts of tertiary amines and their N-oxides.
abstract: A series of model tertiary amines were oxidized in situ in an NMR tube to amine N-oxides and their (1)H and (13)C NMR spectra were recorded. Next, the chemical shifts induced by oxidation (Δδ) were calculated using different GIAO methods investigating the influence of the method [Hartree-Fock (HF), Moeller-Plesset perturbation, density functional theory (DFT)], the functional applied in the DFT (B3LYP, BPW, OPBE, OPW91) and the basis set used [6-31G*, 6-311G**, 6-311 + + G** and 6-311 + + G(3df,3pd)]. The best results were obtained with the HF/6-311 + + G** and OPBE/6-311 + + G** methods. The computation/experiment comparison approach was used for the configuration prediction of chiral amine N-oxides-(R) and (S)-agroclavine-6-N-oxide.
authors: Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, Czech Republic.
authors: Radek
authors: R
authors: Pohl
authors: Martin
authors: M
authors: Dračínský
authors: Lenka
authors: L
authors: Slavětínská
authors: Miloš
authors: M
authors: Buděšínský
mesh_terms: D000588:Amines / Q000737:chemistry*; D002247:Carbon Isotopes; D009682:Magnetic Resonance Spectroscopy / Q000592:standards; D008958:Models, Molecular; D015394:Molecular Structure; D010087:Oxides / Q000737:chemistry*; D016062:Porosity; D012015:Reference Standards; D013237:Stereoisomerism
chemical_list: D000588:Amines; D002247:Carbon Isotopes; D010087:Oxides