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A 13C NMR study of hindered rotation in N1,N1-penta- and N1, N1-hexa-methylene-N2-substituted-phenylformamidines

✍ Scribed by Iwona Wawer

Publisher
John Wiley and Sons
Year
1987
Tongue
English
Weight
388 KB
Volume
25
Category
Article
ISSN
0749-1581

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✦ Synopsis

Rates of rotations about the C-N' partial double bond in a series of six N',N' penta-and six N',N'-hexa-methylene-Nz-substituted-phenyformamidines were determined from 13C DNMR line shape analysis.

Electron accepting substituents at the phenyl ring increase the barrier to rotation, and electron donating substituents decrease the barrier, compared with the nonsubstituted compound. Linear relationships are shown to exist between AG* and the I3C chemical shifts of the functional carbon or the pK, of formamidines.

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