New axially chiral amine organocatalysts

Organocatalysis has become one of the most popular areas of research within organic chemistry over the past 15 years. This is due to the fact that, usually under mild conditions, it is possible to access either highly functionalized or previously inaccessible structural motifs using this relatively new type of catalysis. Firstly, methodology is reported for the synthesis and use of tertiary amine organocatalysts based on the now ubiquitous binaphthyl backbone. The tertiary amines synthesized were shown to be effective nitrogen transfer reagents in the asymmetric aziridination of chalcone substrates, with enantiomeric excesses of up to 37% seen. The first example of an isolated chiral hydrazinium salt being used as a nitrogen transfer reagent for the aziridination of enones is also described. Secondly, a range of α-substituted secondary amines based on the binaphthyl backbone has been synthesized from easily accessible iminium salts. Preliminary catalyst testing showed them to be interesting alternatives to the more commonly seen proline-derived catalysts for asymmetric conjugate additions reactions between cyclic enones and malonates, with enantiomeric excesses of 24% seen using optimized conditions