AB INITIO STUDY OF THE EFFECT OF CH-CENTER-DOT-CENTER-DOT-CENTER-DOT-O HYDROGEN BONDING ON THE EXO/ENDO STEREOSELECTIVITY OF DIELS-ALDER REACTIONS OF 2-SUBSTITUTED-1,3-DIENES WITH SULFUR DIOXIDE

摘要

Ab initio calculations at the MP2/6-31G*//HF/3-21G* level have been carried out to study Diels-Alder reactions of 2-substituted-1,3-dienes with sulfur dioxide. The CH ... O electrostatic interaction detected in some of the transition structures located could be decisive in the control of the exo/endo stereoselectivity of this type of reaction. (C) 1996 John Wiley & Sons, Inc. [References: 25]