D i CE: Diastereomeric in Silico Chiral Elucidation, Expanded DP4 Probability Theory Method for Diastereomer and Structural Assignment

作者：Dongyue Xin, Paul‐James Jones, Nina C. Gonnella · 发表于：The Journal of Organic Chemistry · 年份：2018 · DOI：10.1021/acs.joc.8b00338 · 被引用次数：53 · 研究领域：Molecular spectroscopy and chirality、Analytical Chemistry and Chromatography、Metabolomics and Mass Spectrometry Studies

NMR chemical shift prediction at the B3LYP/cc-pVDZ level of theory was used to develop a highly accurate probability theory algorithm for the determination of the stereochemistry of diastereomers as well as the regiochemistry. DFT-GIAO calculations were performed for each conformer using geometry optimization and a CPCM solvent model. Boltzmann averaged shielding constants were converted to chemical shifts for 1 H and 13 C, using the generalized linear scaling terms determined in four different solvents for 1 H and 13 C and extended to 15 N in DMSO. The probability theory algorithm, D i CE, was based on the DP4 method and developed for 1 H, 13 C, and 15 N NMR using individual and combined probability data. The chemical shift calculation errors were fitted to a Student’s t -distribution for 1 H and 13 C and a normal distribution for 15 N. The application yielded a high accuracy for structural assignment with a low computational cost.