Diaza-crown ethers—VI : A mechanism for metal ion promoted formation of macrocyclic diazaoligoethers

The mechanism of the formation of 1,7,10,16-tetraoxa - 4,13 - diazacylooctadecane has been studied from both a thermodynamic and a kinetic point of view. The cyclisation is favoured by the presence of an alkali metal ion, which forms a complex with the ring precursor. Both this intermediate and the complex react with starting material, but only the complex forms a cyclic product. The rate constants of these reactions have been determined by using simulation methods.