Proton Magnetic Resonance Spectra, Conformational Preferences, and Approximate Molecular Orbital Calculations for the syn and anti 2-Furanaldoximes

摘要: Evidence is adduced, mainly from proton chemical shift and long-range coupling constant data, that the anti isomer of 2-furanaldoxime exists almost exclusively in s-cis form solution, independently type intermolecular association occurs. Intramolecular hydrogen bonding apparently absent this isomer. Similarly, syn roughly equal mixtures s-trans forms solvents widely different polarities. A variety nuclear spin–spin constants are calculated via INDO CNDO molecular orbital approximations, as dipole moments conformational energies, for 2-furanaldehyde its oximes. On whole experimental trends well reproduced by computations.