Tn. Aksamentova et al., Dipole moments and molecular conformations of O-vinyl- and O-ethylacetoximes in solutions, RUSS CHEM B, 48(9), 1999, pp. 1664-1669
Dipole moments of the molecules of O-vinyl- and O-ethylacetoximes in octane
and THF were measured at different temperatures. In octane, the equilibriu
m mixture of stable O-vinylacetoxime conformers consists of forms with diff
erent polarity. Polarity of these conformers, which are due to rotation abo
ut the C-O and N-O bonds, is mainly determined by the relative position of
the lone electron pairs of nitrogen and oxygen atoms. The fraction of the p
olar conformer increases, as temperature increases, as well as on going fro
m octane to THF. Saturation of the vinyl group in the O-vinylacetoxime mole
cule nearly halves the molecular dipole moment in the nonpolar medium, whic
h radically differentiates this compound from vinyl ethers.