摘要
The structure of （E）-N-[（E）-3-[（lR,2R）-2-（3,4-dibromo-phenyl）-l-fluro-cyclopropyl]- allylidene]-2-0-tolyl-acetamide （C21HIsONFBrz, Mr = 479.18） has been determined by X-ray single- crystal diffraction and theoretical calculations to establish the configuration, stereochemistry and a stable conformation of the molecule. The compound crystallizes in the monoclinic space group P21/c, a = 28.3452（10）, b = 4.9311（10）, c = 14.257（2） A, fl = 102.7654（10）, V = 1943.5（5） A3 and Z = 4. The structure has been refined to the final R = 0.05 for the observed structure factors with 1 〉 30（/）. Theoretical calculations in the ground state have been carried out for the compound studied using the Hartree-Fock （HF） and density functional theory （DFT） （B3LYP） with 6-31G（d,p） basis sets. The results show that the studied compound prefers the keto form. The compound involves intra- and intermolecular hydrogen bonding of C-H.-.O and C-H-..F types, which further stabilize the structure and display a trans configuration for the C=N and C=C double bonds. The calculated results show that the predicted geometry can well reproduce the structural parameters.
The structure of （E）-N-[（E）-3-[（lR,2R）-2-（3,4-dibromo-phenyl）-l-fluro-cyclopropyl]- allylidene]-2-0-tolyl-acetamide （C21HIsONFBrz, Mr = 479.18） has been determined by X-ray single- crystal diffraction and theoretical calculations to establish the configuration, stereochemistry and a stable conformation of the molecule. The compound crystallizes in the monoclinic space group P21/c, a = 28.3452（10）, b = 4.9311（10）, c = 14.257（2） A, fl = 102.7654（10）, V = 1943.5（5） A3 and Z = 4. The structure has been refined to the final R = 0.05 for the observed structure factors with 1 〉 30（/）. Theoretical calculations in the ground state have been carried out for the compound studied using the Hartree-Fock （HF） and density functional theory （DFT） （B3LYP） with 6-31G（d,p） basis sets. The results show that the studied compound prefers the keto form. The compound involves intra- and intermolecular hydrogen bonding of C-H.-.O and C-H-..F types, which further stabilize the structure and display a trans configuration for the C=N and C=C double bonds. The calculated results show that the predicted geometry can well reproduce the structural parameters.
