This data set comprises the optimised structures (ground state and transition states) for the molecules discussed in Chapter 5--Understanding enantioselectivity in an aza-Darzens reaction. In addition, a spread sheet containing the list of all the molecules along with the full list of energies (as well as negative eigenvalues for transition states) is presented. The optimised structures relevant to each section of the chapter are organised in different folders and are listed herein: --5.2: Proposing a mechanistic picture-- *intermediate complexes *starting materials *uncatalysed TSs --Model catalyst approach: Activation modes-- *model catalyst TSs --Full catalyst approach: Enantioselectivity-- *12-addition TSs-ONIOM *elimination TSs-ONIOM *TRIP-ONIOM *product