Novel applications of bifunctional iminophosphorane superbases in enantioselective catalytic methodology

Chapter 1 introduces enantioselective organocatalysis with a specific focus on bifunctional catalysts and chiral superbases. Subsequently, the discovery and applications of bifunctional iminophosphorane (BIMP) catalysts will be described. Chapter 2 focuses on the development of a novel enantioselective sulfa-Michael addition employing alkenyl-benzimidazoles as electrophiles. The work in this chapter will showcase a rare example of organocatalysed enantioselective addition to alkenyl heterocycles for the rapid generation of 3-D druglike scaffolds. Chapter 3 introduces approaches to enantioselective P(V) synthesis, highlighting the strengths and shortcomings of current methods to then focus on the development of an unprecedented enantioselective nucleophilic desymmetrisation of phosphonate esters. The unique ability of a novel ureidopeptide BIMP catalyst to promote this reaction enantioselectively will be demonstrated against a wide array of other BIMPs as well as Chinchona alkaloid and phase transfer catalysts. The downstream utility of the desymmetrised product will be demonstrated in the synthesis of numerous attractive nucleoside derived compounds. Chapter 4 will disclose an improved enantioselective nucleophilic desymmetrisation of P(V) containing species. Via a superior BIMP catalyst scaffold and a thiazolidinone leaving group on the P(V) electrophiles, higher enantioselectivities, lower catalyst loadings, and improved nucleophile scope were obtained.