6130-92-3Relevant articles and documents
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Mackay,Waters
, p. 813,814 (1966)
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Roberts,Ingold
, p. 3228,3233 (1973)
Conformational Studies by Dynamic Nuclear Magnetic Resonance. Part 20. Internal Motion in Hydrazones and Related Derivatives
Lunazzi, Lodovico,Macciantelli, Dante
, p. 604 - 609 (2007/10/02)
Restricted rotation about the N-N bond in unhindered, non-conjugated hydrazones (e.g.Me2N-N=CH2) has been detected by 13C n.m.r. below -150 degC.The results indicate that the N=C plane is coplanar with the dynamically averaged plane of the sp3 nitrogen, in contrast with hindered hydrazones (containing the 2,2,6,6-tetramethylpipridinyl ring, TMP) where the N=C moiety adopts a perpendicular conformation.Effects due to the slowing of ring reversal were not observed in hydrazones containing the TMP ring, but were detected in other hindered derivatives such as TMP-NH2 and TMP-NO.A most interesting feature becomes apparent in two hydrazones with the 2,6-cis-dimethylpiperidinyl (DMP) ring, DMP-N=CH2 and DMP-N=CHPh.In the same molecule the N=C moiety is coplanar with the averaged sp3 nitrogen plane when the methyls are axial, but perpendicular when the methyls are equatorial.