Efficient synthesis of novel N-substituted 2-carboxy-4-quinolones via lithium bis(trimethylsilyl)amide (LiHMDS)-induced in situ cyclocondensation reactionElectronic supplementary information (ESI) available. CCDC 1470319 (3c) and 1470320 (3e). For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c6ra28631c

A different approach for the synthesis of N -substituted 2-carboxy-4-quinolones using direct reductive amination followed by LiHMDS-induced cyclocondensation has been developed. A range of analogues of the title compounds with broad substrate scope were obtained in moderate yields and good regioselectivity. Efficient synthesis of N -aryl-2-carboxy-substituted 4-quinolones with broad substrate scope and high regioselectivity.