A study of the behaviour of some electron-rich 2-methyleneindolines (1–3) with different electron-poor reagents (formation of new carbon–carbon and nitrogen–carbon bonds) has furnished interesting results from both synthetic and the mechanistic viewpoints. Enamines 1– 3 have been reacted with the β-nitroenamines 4–7 (reaction CeCl3· 7H2O promoted), giving the polymethine dyes 14–23. The same bases 1–3 have been nitroalkylated with the ...
