Synthesis of some new bis-Schiff bases of isatin and 5-fluoroisatin in a water suspension medium.

Condensation of aromatic primary bis-amines with isatin (1H-indole-2,3-dione) and 5-flouroisatin occurred cleanly and efficiently in a water suspension medium without using any organic solvent or acid catalyst. The corresponding bis-Schiff bases were obtained in good yields and were easily isolated by filtration. Their structures were confirmed by (1)H-NMR, (13)C-NMR, IR and mass spectra.