ChemInform Abstract: A STUDY OF THE Π-POLARIZATION EFFECT: CARBON-13 NUCLEAR MAGNETIC RESONANCE CHEMICAL SHIFTS AND SCF ELECTRON POPULATIONS IN 1-SUBSTITUTED 4-PHENYLBICYCLO(2.2.2)OCTANES

Carbon-13 and proton chemical shifts have been measured for several monosubstituted isothiazoles. Substituent effects upon these chemical shifts are compared with those observed for monosubstituted benzenes, pyridines, and thiophenes. In general the observed substituent effects in the isothiazoles and thiophenes closely parallel one another. Correlations between the observed carbon-13 Chemical shifts and CNDO/2 calculated charge densities are examined.

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Studies of specifically fluorinated carbohydrates. Part I. Nuclear magnetic resonance studies of hexopyranosyl fluoride derivatives

Canadian Journal of Chemistry ◽

10.1139/v69-001 ◽

1969 ◽

Vol 47 (1) ◽

pp. 1-17 ◽

Cited By ~ 122

Author(s):

L. D. Hall ◽

J. F. Manville ◽

N. S. Bhacca

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Angular Dependence ◽

Chemical Shifts ◽

Relative Orientation ◽

Coupling Constants ◽

Pyranose Ring ◽

Spectral Parameters ◽

Magnetic Resonance Studies ◽

Nuclear Magnetic

A detailed study has been made of both the 1H and 19F nuclear magnetic resonance (n.m.r.) spectra of a series of hexopyranosyl fluoride derivatives. Some of the 1H spectra were measured at 220 MHz. The 1H spectral parameters define both the configuration and the conformation of each of these derivatives. Study of the 19F n.m.r. parameters revealed several stereospecific dependencies. The 19F chemical shifts depend upon, (a) the orientation of the fluorine substituent with respect to the pyranose ring and, (b) the relative orientation of other substituents attached to the ring; for acetoxy substituents, these configurational dependencies appear to be additive. The vicinal19F–1H coupling constants exhibit a marked angular dependence for which Jtrans = ca. 24 Hz whilst Jgauche = 1.0 to 1.5 Hz for [Formula: see text] and 7.5 to 12.6 Hz for [Formula: see text] The geminal19F–1H couplings depend on the orientation of the substituent at C-2; when this substituent is equatorial JF,H is ca. 53.5 Hz and when it is axial the value is ca. 49 Hz.

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Nuclear magnetic resonance chemical shifts of cyclopropane HCH in unsubstituted bicyclo[X.1.0]alkanes as a function of ring size

The Journal of Organic Chemistry ◽

10.1021/jo01270a117 ◽

1968 ◽

Vol 33 (6) ◽

pp. 2587-2589 ◽

Cited By ~ 11

Author(s):

James G. Traynham ◽

John S. Dehn ◽

Ernest E. Green

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Chemical Shifts ◽

Ring Size ◽

Nuclear Magnetic

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The metal nuclear magnetic resonance spectra of some tin(II) and lead(II) complexes with polydentate phosphines

Canadian Journal of Chemistry ◽

10.1139/v83-307 ◽

1983 ◽

Vol 61 (8) ◽

pp. 1795-1799 ◽

Cited By ~ 13

Author(s):

Philip A. W. Dean

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Nmr Spectra ◽

Narrow Range ◽

Chemical Shifts ◽

Nuclear Magnetic Resonance Spectra ◽

Magnetic Resonance Spectra ◽

Nuclear Magnetic

The previously reported 1:1 complexes formed in MeNO2, between M(SbF6)2 (M = Sn or Pb) and Ph2P(CH2)2PPh2, PhP[(CH2)2PPh2]2, MeC(CH2PPh2)3, P[(CH2)2PPh2]3, and [Formula: see text] have been studied by metal (119Sn or 207Pb) nmr. The metal chemical shifts span the comparatively narrow range of −586 to −792 ppm and 60 to −269 ppm, relative to the resonance of MMe4, for 119Sn and 207Pb nmr, respectively. The implications of these data regarding the denticity of the ligand in M(P[(CH2)2PPh2]3)2+ are discussed, and a comparison with the metal nmr spectra of related stannous and plumbous complexes is made.

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