排序方式: 共有74条查询结果,搜索用时 31 毫秒
71.
A simple, general, and highly regioselective procedure has been developed for the one-pot synthesis of β-hydroxysulfides in good yields from various styrenes and disulfides by cleavage of the S-S bond with a Zn/AlCl3 system in aqueous acetonitrile at 80 °C and in the presence of oxygen. 相似文献
72.
Russian Journal of General Chemistry - In this study, the reaction of 1-alkyl-5-nitro-1H-benzoimidazoles and 1-alkyl-5-nitro-1H-indazoles with benzofuran and benzothiophen derivatives has led to... 相似文献
73.
Mozhgan Khorasani-Motlagh Nasser Safari Hamid Reza Khavasi Meissam Noroozifar Hashem Shahroosvand Mahtab Biabani 《Journal of chemical crystallography》2007,37(7):457-461
Exposure of dichloromethane solution of [OEOPFe(BF4)], where OEOP is the monoanion of octaethyloxoporphyrin, to dioxygen results in its transformation into the μ-oxo bridged compound, [(OEOPFe)2O)](BF4)2. The molecular structure of the title compound, [(OEOPFe)2O](BF4)2, was determined by single-crystal X-ray diffraction. It contains a binuclear centrosymmetric [(OEOPFe)2O]2+ cation (the bridging O atom lies on an inversion centre) and two tetrafluoroborate anions. The Fe atom is five-coordinate to four N atoms of the porphyrin ring and to one bridging O atom. The compound is characterized by an average Fe–N bond length of 2.064 Å. The Fe–O bond distance is 1.7665(11) Å and the Fe–O–Fe bond angle is 180.0° and the two porphyrin rings are parallel. Crystal data: crystal system, monoclinic, a = 8.867(3), b = 26.104(9), c = 15.748(6) Å, β = 105.40(3)°, space group, P21/c, V = 3514(2) Å3, Z = 2. 相似文献
74.
Shahamirian M Cyrański MK Krygowski TM 《The journal of physical chemistry. A》2011,115(45):12688-12694
Optimization of monosubstituted (X = NO, NO(2), CN, CHO, Me, OMe, OH, NH(2), NHMe, and N(Me)(2)) derivatives of 1,2- and 2,3-naphthoquinone by use of B3LYP with the 6-311+G** basis set applying the GAUSSIAN03 program allowed us to analyze the character of interactions between the substituents and the carbonyl groups. It is shown that only one of two carbonyl groups exhibited substantial substituent effect evidenced by regression of the CO bond length and delocalization index, DI(CO) on the Hammett substituent constants, σ(p), with a very high correlation coefficient, whereas the other one did not depend in any substantial way on σ(p). Dependences of conjugation path built up of bonds between substituent and oxygen atoms of carbonyl groups on σ(p), give more acceptable correlations if the number of bonds in the path is even than in cases when they are odd. 相似文献