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Prediction of 19F NMR Chemical Shifts for Fluorinated Aromatic Compounds.

ABSTRACT: Scaling factors are reported for use in predicting 19F NMR chemical shifts for fluorinated (hetero)aromatic compounds with relatively low levels of theory. Our recommended scaling factors were developed using a curated data set of 52 compounds, with 100 individual 19F shifts spanning a range of 153 ppm. With a maximum deviation of 6.5 ppm between experimental and computed shifts, or 4% of the range tested, these scaling factors allow for the assignment of chemical shifts to specific fluorines in multifluorinated aromatics. The utility of this approach is highlighted by several structural reassignments.

SUBMITTER: Saunders C

PROVIDER: S-EPMC6025806 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Prediction of 19F NMR Chemical Shifts for Fluorinated Aromatic Compounds.

Saunders Carla C Khaled Mohammad B MB Weaver Jimmie D JD Tantillo Dean J DJ

The Journal of organic chemistry 20180226 6

Scaling factors are reported for use in predicting 19F NMR chemical shifts for fluorinated (hetero)aromatic compounds with relatively low levels of theory. Our recommended scaling factors were developed using a curated data set of 52 compounds, with 100 individual 19F shifts spanning a range of 153 ppm. With a maximum deviation of 6.5 ppm between experimental and computed shifts, or 4% of the range tested, these scaling factors allow for the assignment of chemical shifts to ...[more]

PMID: 29470063

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