Ab initio investigations of the geometric conformation of glycidic methyl esters and the related complexes with a lithium cation: a contribution to the understanding of regioselective openings of these esters with lithium reagents

Abstract In order to contribute to the understanding of the regioselective epoxide ring opening by lithium organometallic reagents, ab initio calculations have been performed on the methyl glycidate, the methyl trans -3-methyl-glycidate, the methyl cis -3-methyl-glycidate and their complexes with a lithium cation. All structural parameters were optimized at the RHF/6-31G ∗ level for the six compounds. The effects of methyl substitution at C 3 , and/or chelation with Li + , on geometry and net atomic charges are discussed. The present results suggest that the steric factor might contribute to explain the regioselective epoxide ring opening by lithium organometallic reagents such as cuprates.