Substituent effect on transition structure of Corey-Chaykovsky reaction: Asemiempirical study

Effect of various substituents on the conformation of transition structures of Corey-Chaykovsky reaction has been studied by semiempirical quantum mec hanical method. It has been observed that steric effect and frontier intera ction between substituent pi electron and sulphur lone pair play a prominen t role in determining the actual conformation of transition stares. Based o n the energy of the transition states, a probable explanation for showing h igh stereoselectivity of aromatic reagents involved in the above reaction h as also been proposed.