A proton spin–lattice relaxation rate and nuclear Overhauser effect investigation of the stereochemistry of some 1-aryl derivatives of 1,2-dihydro-s-triazines

✍ Scribed by Sriyawathie Peiris; Lawrence D. Colebrook

• Publisher: John Wiley and Sons
• Year: 1984
• Tongue: English
• Weight: 536 KB
• Volume: 22
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1270220407

✦ Synopsis

Proton spin-lattice relaxation rates (Rl values) have been measured, at 400 MHz, for a number of 2-methyland 2,2-dimethyl-substituted 4,6-diamino-l-aryl-l,2-dihydro-s-~es. These compounds have high barriers to internal rotation about the aryl C-N bond, and exist in solution as mixtures of enantiomeric or diastereomeric rotational isomers. Diastereotopically related 2-methyl groups in enantiomeric rotamers, and 2-methyl and 2-methine protons in diastereomeric rotamers, typically have Merent relaxation rates. In favourable circnmstances this information may be used to identify the individual rotamers. U n e q n i v d direct identitication of rotamers may be obtained from nuclear Overhauser effect difference spectra.