학술논문
Accuracy vs Time Dilemma on the Prediction of NMR Chemical Shifts: A Case Study (Chloropyrimidines).
Document Type
Article
Author
Source
Subject
*NUCLEAR magnetism
*QUANTUM chemistry
*PHYSICAL & theoretical chemistry
*SOLVENTS
*SOLUTION (Chemistry)
*CHEMISTRY
*
*
*
*
*
Language
ISSN
0022-3263
Abstract
The nuclear magnetic shieldings of two chloropyrimidine species have been predicted and analyzed by means of ab initio and DFT methods. The results have been compared with the experimental values and with those from other database-related approaches. These dataset-based techniques are found to be particularly valuable because of the accurate and instantaneous prediction of the 13C chemical shifts. On the other hand, only a few quantum chemistry based approaches were showed to be the most precise to predict ¹H chemical shifts and to elucidate unequivocally the ¹H NMR spectra of the regioisomeric mixture under study. Special emphasis was put on incorporating the solvent effect, implicitly, or explicitly. The influence of the level of theory and basis set in the predicted values has also been discussed. [ABSTRACT FROM AUTHOR]