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13C NMR study of some polychloro-isobutane and -isobutene compounds

✍ Scribed by Maija Pitkänen; Katri Laihia; Klaus Schulze

Publisher
John Wiley and Sons
Year
1984
Tongue
English
Weight
248 KB
Volume
22
Category
Article
ISSN
0749-1581

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✦ Synopsis

The =C chemical shifts and the carbon-proton coupling constants have been determined for some chlorinated isobutane and isobutene compounds. The one-bond coupling constants in isobutane derivatives showed a regular increase with an increasing number of y-chlorine substituents. The three-bond coupling constant of the methyl carbon decreased from 4 3 to 2.0Hz as the number of chlorine substituents in the y-position increased. In tbe isobutene compounds, the vicinal coupling of C -l was larger to protons in a group that is trans with respect to a chlorine substituent on C-1 than to those in the corresponding group cis to the chlorine. The vicinal coupling constants between atoms in geminal groups (on C-2) seem to be affected by the orientation of the chlorine substituent on C-1.

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