Preparation and some spectral properties of benzo-fused 1,4-dimethyl-2(1H)-quinolinones†

The preparation of the angular and linear isomers of benzo-fused 1,4-dimethyl-2(1H)-quinolinones 3a–5a and their spectral data including 13C-nmr data are reported. Structural difference among 3a–5a is confirmed from the proximity effect in 1H- and 13C-nmr data and from the uv spectral pattern.