Development of bifunctional organic superbases for catalytic enantioselective synthesis

Thesis

Chapter I describes the concept of chirality and enantioselective synthesis. Organocatalysis is then introduced, with a focus on bifunctional organocatalysis and superbases in asymmetric methodology. Finally, bifunctional iminophosphorane catalysis is introduced and discussed.

Chapter II describes the development of the first organocatalytic conjugate addition to unactivated α,β-unsaturated amides, exemplified by a highly enantioselective sulfa-Michael addition, and along with that the development of 3rd generation BIMP catalysts.

Chapter III describes the development of the direct catalytic enantioselective conjugate addition of nitroalkanes to unactivated α,β-unsaturated esters, and the enantioselective synthesis of a range of APIs.

Chapter IV discusses the NMR-aided pKBH+ measurements used to determine the basicity of iminophosphoranes. Furthermore, it describes a newly developed, analogous, but more rapid method for the determination of pKBH+ values, as well as the synthesis of a highly basic iminophosphorane.

Chapter V contains the references for previous chapters. Chapter VI and Chapter VII contain the experimental details and analytical data of procedures and products described in Chapter II and Chapter III, and the Appendix contains synthetic information related to Chapter IV.

Authors: Rozsar, D

• DOI: 10.5287/ora-vj4ryqa1g
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: squaramide; Michael addition; superbase; organocatalysis; bifunctional iminophosphorane; BIMP; enantioselective catalysis
• Subjects: Chemistry, Organic; Homogeneous catalysis; Enantioselective catalysis