6533b85efe1ef96bd12bfbee

RESEARCH PRODUCT

1H,13C and17O NMR study of chlorovanillins and some related compounds

Erkki KolehmainenJuha KnuutinenKatri LaihiaJ. Hyötyläinen

subject

chemistry.chemical_classificationCoupling constantProtonCarbon-13 NMR satelliteStereochemistryChemical shiftGeneral ChemistryNuclear magnetic resonance spectroscopyDihedral angleAldehydeCrystallographychemistryGroup (periodic table)General Materials Science

description

1H, 13C and 17O NMR chemical shifts and nJ(H,H), 1J(C,H) and 3J(C-6, H-formyl) spin—spin coupling constants of chlorinated vanillins (3-methoxy-4-hydroxybenzaldehydes) were determined. The variation in the long-range 4J(H,H) value between the formyl proton and an ortho-proton suggests that the ortho-substituent strongly forces the formyl group out of the aromatic plane. This can also be observed by considering the 3J(C-6,H-formyl) values and the 13C and 17O NMR chemical shifts. The 17O NMR chemical shifts show a linear correlation with the torsion angle of the formyl group calculated by molecular mechanics. The 13C and 17O NMR chemical shifts of the methoxyl group also possess strong predictive power in estimating the torsional characteristics of this group.

yearjournalcountryeditionlanguage
1992-03-01Magnetic Resonance in Chemistry
https://doi.org/10.1002/mrc.1260300311