University Chemistry ›› 2022, Vol. 37 ›› Issue (3): 2106004.doi: 10.3866/PKU.DXHX202106004

• Survey of Chemistry • Previous Articles     Next Articles

Explanation of the Transition State Theory of the Stereoselectivity of the Reduction of Substituted Cyclohexanone

Jia Li, Xiao Hu, Jianchun Wang, Kaige Yu, Shining Geng, Xiangfu Meng()   

  • Received:2021-06-03 Accepted:2021-09-23 Published:2021-10-13
  • Contact: Xiangfu Meng E-mail:xfmeng@cnu.edu.cn

Abstract:

It is inaccurate to only predict the kinetic conditions of the reducing reagent and the thermodynamic stability of the resulting product during a reduction reaction. Other factors in the reaction need to be considered. Transition state theory can be used to comprehensively and accurately predict the stereoselectivity of the products formed during the reduction of substituted cyclohexanones. On the one hand, when the reducing agent attacks the carbonyl group to form a transition state, the steric hindrance and electronic effects determine the stereoselectivity of the reaction. On the other hand, the predominant conformation of the reactant, i.e., the torsional strain when the transition state is formed and the deflection angle relative to the standard cross conformation, cannot be ignored in regard to the stereoselectivity of the product. This article discusses the steric hindrance, electronic effects, and conformation during the formation of the transition state, and explains the stereoselectivity of the reduction products formed during the reduction of substituted cyclohexanones.

Key words: Substituted cyclohexanone, Reduction, Stereoselectivity, Transition state, Theoretical explanation