Generation and Reactivity of C(1)-Ammonium Enolates by Using Isothiourea Catalysis

C(1)-Ammonium enolates are powerful, catalytically generated synthetic intermediates applied in the enantioselective alpha-functionalisation of carboxylic acid derivatives. This minireview describes the recent developments in the generation and application of C(1)-ammonium enolates from various precursors (carboxylic acids, anhydrides, acyl imidazoles, aryl esters, alpha-diazoketones, alkyl halides) using isothiourea Lewis base organocatalysts. Their synthetic utility in intra- and intermolecular enantioselective C-C and C-X bond forming processes on reaction with various electrophiles will be showcased utilising two distinct catalyst turnover approaches.

Automated summary

Ammonium enolates are powerful synthetic intermediates generated catalytically using isothiourea Lewis base organocatalysts, and have been applied in selective alpha-functionalisation reactions with various precursors. Their utility in intra- and intermolecular C-C and C-X bond forming processes with electrophiles is showcased using different catalyst turnover approaches.