Entwicklung eines neuen enantioselektiven, organokatalytischen Domino-Prozesses zur Dearomatisierung von Phenolderivaten
Zusammenfassung der Projektergebnisse
In this project an alkylative CED-process comprising of the alkylation of a phenol derivative with an intramolecular triple bond as electrophile to the para-position of the aromatic ring followed by a desymmetrising Michael addition with the pendant aldehyde was developed. This process allows the formation of complex, three dimensional products in good overall yield and up to excellent enantiomeric excess from achiral, easily available starting materials. The main aim of this project, the development of optimised reaction conditions regarding yield and enantiomeric excess has been achieved. Until now the developed process is limited to a nitrogen-substituent in the para-position of the anisole. The possibility of using either an aldehyde or acetal as starting material for the enantioselective, organocatalytic, alkylative dearomatisation process was also demonstrated. The use of the acetal as starting material for the CED-process economises not only the overall synthetic sequence, but also simplifies the use of labile aldehydes in this transformation.