USING MOLECULAR GRAPHICS, MOLECULAR MECHA NICS, QUANTUM-CHEMISTRY ANDELECTROSTATIC POTENTIAL METHOD TO STUDY STRUCTURE-PROPERTY RELATIONSHIP ON PESTICIDES .10. STUDY ON INTERNAL-ROTATION PASSAGE IN SULFONYLUREA MOLECULE BY MOLECULAR MECHANICS METHOD

Citation
Al. Liu et al., USING MOLECULAR GRAPHICS, MOLECULAR MECHA NICS, QUANTUM-CHEMISTRY ANDELECTROSTATIC POTENTIAL METHOD TO STUDY STRUCTURE-PROPERTY RELATIONSHIP ON PESTICIDES .10. STUDY ON INTERNAL-ROTATION PASSAGE IN SULFONYLUREA MOLECULE BY MOLECULAR MECHANICS METHOD, Gaodeng xuexiao huaxue xuebao, 18(4), 1997, pp. 574-576
Citations number
4
Categorie Soggetti
Chemistry
ISSN journal
02510790
Volume
18
Issue
4
Year of publication
1997
Pages
574 - 576
Database
ISI
SICI code
0251-0790(1997)18:4<574:UMGMMN>2.0.ZU;2-F
Abstract
In this paper, we have discussed the internal rotation in sulfonylurea molecules, which belong to high active and low toxic herbicides and t ake the form of conformational isomers in their crystal structures. In order to understand the formation of their enantimers, we obtained a series of data of molecular energy of different conformation by using the molecular mechanics method and the stepwise rotation single-bond m ethod. We found out the lowest internal rotation passage and obtained the energy barrier of hindered rotation which is less 60 kJ/mol. This result shows that there is a lower energy passage to exchange the conf ormational isomers of these molecules, so exchanging the different con formational isomers is not very difficult.