The structure of two 1-(nitrophenyl)-D2-pyrazolines: A crystallographic and theoretical study
The crystal and molecular structures of two nitrophenylpyrazolines have been determined. The geometries have been used as starting geometries for density functional theory (DFT) calculations. The differences in conformation between both molecules and between the solid state and gas phase are explained in terms of steric effects. An attractive intramolecular N···N interaction between the nitro group and the pyrazoline N2 nitrogens has been found. Absolute shieldings have been calculated (GIAO) and compared with experimental 1H and 13C chemical shifts.