A molecular mechanics study of the conformational behaviour of some substituted methyl formates

Abstract Molecular mechanics computations are performed for methyl fluoroformate, chloromethyl formate and chloromethyl fluoroformate. Moloecular mechanics parameters, enthalpy difference between s - cis and s - trans conformers, and optimized geometry of the most stable conformers are computed and informations thus obtained is utilised to high light the conformational behaviour of the molecules. The structure of all the molecules obtained by present methodology is well in agreement with the experimentally observed structure. The enthalpy difference and barrier to rotation for all the molecules are not large enough for their physical separation.