Molecular Structure of 3,4-Difluorofuran-2,5-dione (Difluoromaleic Anhydride) As Determined by Electron Diffraction and Microwave Spectroscopy in the Gas Phase and by Theoretical Computations
摘要:
The structure of 3,4-difluorofuran-2,5-dione has been determined experimentally in the gas phase by microwave spectroscopy using rotation constants derived from five isotopomers and by a combined analysis of electron-diffraction and microwave data. The geometry is planar with C-2v symmetry. Structural parameters [distances (r(alpha)degrees)/pm, angles angle(alpha)/deg, (1 sigma errors)] for the combined analysis are: r(C=O) = 119.0(1); r(C-F) = 130.9(2); r-(C=C) = 133.2(3), r(O-C) = 139.3(1); r(C-C) = 148.5(2); angle C-C=C = 108.3(1); angle C=C-F = 129.9(1); angle C-C=O = 129.3(1); angle C-O-C = 108.9(1); angle O-C-C = 107.2(1). These values are in excellent agreement with those obtained in an ab initio study of the molecular geometry at the MP2/6-311+G*(2df) level of theory. The dipole moment of difluoromaleic anhydride has been determined experimentally by Stark-effect measurements to be 1.867(3) D.
Synthesis of hydrohalocyclobutenes through dechlorination of hydrohalocyclobutanes in amide solvents
作者:Wenni Zhang、Fengniu Lu、Chengping Zhang、Qin Guo、Hengdao Quan
DOI:10.1016/j.jfluchem.2020.109506
日期:2020.5
In this study, we synthesized hydrohalocyclobutenes through the dechlorination of hydrohalocyclobutanes in N,N-dimethylformamide and N,N-dimethylacetamide. The structure of the reaction site –CClR1–CClR2– (R1 = H, F; R2 = H, F, Cl) of the reactants was critical for the efficient reductive dechlorination from the 1- and 2- positions. The reaction proceeded efficiently at the –CFCl–CFCl–, –CFCl–CCl2–
Dihydropyridazinones, pyridazinones and related compounds as fungicides
申请人:Rohm and Haas Company
公开号:US05631254A1
公开(公告)日:1997-05-20
This invention relates to substituted dihydropyridazinones, pyridazinones and related compounds, of the formula ##STR1## wherein A, Q, D and R1 are as defined within, compositions containing these compounds and methods of controlling agricultural and mammalian fungal diseases.