Structural characterization of unusually stable polycyclic ozonides
摘要:
The single crystal structure of seven tri- and tetracyclic ozonides derived from 8-oxabicycle[3.2.1]oct-6-en-3-ones have been characterized by X-ray diffraction method. Five ozonides (4, 5, 6,7 and 8) crystallize in the monoclinic crystal system with P2(1)/c space group. Compound 3 crystallize in the unusual centro-symmetric space group R (3) over barm, which represents similar to 0.04% of the total number of structures know. The supramolecular structure of 3 forms infinite channels in a hexagram fashion, resulting in a honeycomb-like structure. Semi-empirical (PM6) and density functional theory methods (DFT) with the B3LYP functional and the 6-31G(d) basis set were used to optimize the geometries and compute structural parameters (bond lengths, angles and dihedral angles) that could be compared to the refined crystal structure. The theoretical results show good agreements with the experimental structure. (C) 2014 Elsevier B.V. All rights reserved.
The single crystal structure of seven tri- and tetracyclic ozonides derived from 8-oxabicycle[3.2.1]oct-6-en-3-ones have been characterized by X-ray diffraction method. Five ozonides (4, 5, 6,7 and 8) crystallize in the monoclinic crystal system with P2(1)/c space group. Compound 3 crystallize in the unusual centro-symmetric space group R (3) over barm, which represents similar to 0.04% of the total number of structures know. The supramolecular structure of 3 forms infinite channels in a hexagram fashion, resulting in a honeycomb-like structure. Semi-empirical (PM6) and density functional theory methods (DFT) with the B3LYP functional and the 6-31G(d) basis set were used to optimize the geometries and compute structural parameters (bond lengths, angles and dihedral angles) that could be compared to the refined crystal structure. The theoretical results show good agreements with the experimental structure. (C) 2014 Elsevier B.V. All rights reserved.
Synthesis and Biological Evaluation of New Ozonides with Improved Plant Growth Regulatory Activity
作者:Luiz C. A. Barbosa、Célia R. A. Maltha、Raphael C. Cusati、Róbson R. Teixeira、Filipe F. Rodrigues、Antônio A. Silva、Michael G. B. Drew、Fyaz M. D. Ismail
DOI:10.1021/jf902540z
日期:2009.11.11
The iron oxyallyl carbocation generatedfrom 2,7-dibromocycloheptanone was induced to undergo [4 + 3] cycloaddition reactions with various furans, affording a series of 12-oxatricyclo-[4.4.1.12,5]-dodec-3-en-11-one adducts. Similar methodology was used to prepare two additional cycloadducts using menthofuran and two homologous aliphatic dibromoketones. Dipolar cycloaddition of ozone to the adducts