Synthesis of novel 6,6'-methylene-bis-[3-(2-anilinoacetyl)-4-hydroxycoumarin] derivatives.

The synthesis of novel 6,6'-methylene-bis-[3-(2-anilinoacetyl)-4-hydroxycoumarin] derivatives 6a-f was achieved in excellent yields from 6,6'-methylene-bis-[3-(2-bromoacetyl)-4-hydroxycoumarin] 5 and various arylamines. 5,5'-Methylene-bis-ethylsalicylate 3 was obtained by the esterfication of 5,5'-methylene-bis-salicylic acid 2 with ethanol, which was in turn obtained from salicylic acid 1 and formaldehyde. Cyclocondensation of 3 with ethyl acetoacetate resulted in 6,6'-methylene-bis-[3-acetyl-4-hydroxycoumarin] 4, which on selective alpha-bromination with molecular bromine in the presence of montmorillonite K10-AlCl(3) catalyst, in chloroform-ethyl acetate binary solvent mixture at room temperature, afforded the compound 5 in excellent yield. All the newly synthesized compounds were characterized by their spectral data.