Complete Prediction of the 1H NMR Spectrum of Organic Molecules by DFT Calculations of Chemical Shifts and Spin–Spin Coupling Constants

✍ Scribed by Alessandro Bagno

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 161 KB
• Volume: 7
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/1521-3765(20010417)7:8<1652::aid-chem16520>3.0.co;2-v

✦ Synopsis

1H NMR chemical shifts and coupling constants for several aromatic and aliphatic organic molecules have been calculated with DFT methods. In some test cases (furan, o-dichlorobenzene and n-butyl chloride) the performance of several functionals and basis sets has been analyzed, and the various contributions to spin-spin coupling (Fermi-contact, diamagnetic and paramagnetic spin-orbit) have been evaluated. The latter two components cancel each other, so that the calculation of the contact term only is sufficient for an accurate evaluation of proton-proton couplings. Such calculated values are used to simulate the 1H NMR spectra of organic molecules with complicated spin systems (e.g. naphthalene, o-bromochlorobenzene), obtaining a generally very good agreement with experimental spectra with no prior knowledge of the involved parameters.