Coupling constants fluorine

Emsicy, J W Phillips L, Wray V Fluorine Coupling Constants Pergamon Press Oxford, U K New York 674... 

J. W. Emsley, L. Phillips, and V. Wray, Fluorine Coupling Constants, Prog. NMR Spec-trosc., 10 (1976) 83-756. 

Gillespie, R. J., Hartman, J. S., Parekh, M. Solvent Effects on the Boron-Fluorine Coupling Constant and on Fluorine Exchange in Tetrafluoroborate Anion. Can. J. Chem. 46, 1601 (1968). 

Other hand, fluorine coupling constants are very large and, if this element is present, its coupling can be very useful in interpreting spectra and determining structural relationships including those via nonbonded interactions. ... 

Some typical values of ortho-fluorine coupling constants... 

Table 3.14. Carbon-Fluorine Coupling Constants of Selected Organic Compounds Data from Ref. [115] if not otherwise indicated.

Carbon-Fluorine Coupling Constants in Alkyl and Cycloalkyl Fluorides... 

Table 4.21. Survey of Carbon-Fluorine Coupling Constants (in Hz) in Representative Alkyl and Cycloalkylfluorides [229, 266].

Carbon-fluorine coupling constants of fluorobenzene and selected substituted derivatives are collected in Table 4.60 [402], Benzenoid JCF couplings are about 245+15 Hz. They depend on both type and position of the substituents Electron withdrawing groups increase while electron releasing ones decrease one-bond carbon-fluorine coupling in fluorobenzene, particularly when they are ortho and para to fluorine. These observations can be explained by cannonical resonance formulae which take ( + )- and (-)-M effects into account. The data of fluoroanilines (( + )-M) and fluorobenzaldehydes (( — )-M) provide typical examples (Table 4.60). 

Table 4.70. Carbon-Fluorine Coupling Constants of Isomeric Fluoropyridines and of 2-Fluoropurine (in Hz) [469]. If available, Couplings of the Protonated Heterocycles are Printed in Parentheses.

Table A3.8 Characteristic coupling constants of protons with other nuclei (Hz) Proton-fluorine coupling constants...

F Chemical Shifts of Some Fluorine-Containing Compounds Fluorine Coupling Constants... 

Emsley, J.W., Phillips, L., and Wray, V., Fluorine Coupling Constants, Pergamon, New York, 1977. 

The following table gives the most important fluorine coupling constants, namely, JFN, JFCF, and JCF, together with some typical examples.1-9 The coupling constant values vary with the solvent used.3 The book by Emsley et al.1 gives a complete, detailed list of various compounds. 

C. Direct Carbon-Hydrogen and Carbon-Fluorine Coupling Constants References... 

The geminal proton-fluorine coupling constant 64.90 Hz in fluorocyclopropane was determined by Scherr and Oliver the trans = 9.87 Hz and its cis counterpart HgF = 21.02 Hz were found to have the same relative sign. Other examples of values... 

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