【摘 要】
：
Cis-trans isomerization of [9]-annulenanion(1) and its 2-fluoro-,2-chloro-and 2-bromo-derivatives(2,3 and 4,respectively) were investigated at the HF/6-31G* and
【机 构】
：
Pharmaceutical Sciences Research Center,Department of Medicinal Chemistry,Mazandaran University of M
论文部分内容阅读
Cis-trans isomerization of [9]-annulenanion(1) and its 2-fluoro-,2-chloro-and 2-bromo-derivatives(2,3 and 4,respectively) were investigated at the HF/6-31G* and B3LYP/6-311++G** levels of theory.Cis,cis,cis,cis structures appear more stable than their corresponding cis,cis,cis,trans-isomers.The relative height of energy barriers for cis-trans isomerization is:2cis > 1cis > 3cis > 4cis.This trend for the reverse trans-cis isomerization follows the electronegativity of the substituent at C-2(2trans > 3trans > 4trans > 1trans).
Cis-trans isomerization of [9] -nulenanion (1) and its 2-fluoro-, 2-chloro-and 2-bromo- derivatives (2,3 and 4, respectively) were investigated at the HF / 6-31G * and B3LYP / 6-311 ++ G ** levels of theory .Cis, cis, cis, cis structures appear more stable than their corresponding cis, cis, cis, trans-isomers.The relative height of energy barriers for cis-trans isomerization is : 2cis> 1cis> 3cis> 4cis. This trend for the reverse trans-cis isomerization follows the electronegativity of the substituent at C-2 (2 trans> 3 trans> 4 trans> 1 trans).
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