Synthesis and characterization of a series of 1, x ‐bis‐(4‐oxo‐3,4‐dihydro‐1,2,3‐benzotriazin‐3‐yl)alkanes

Reaction of isatoic anhydride with an alkanediamine in DMF solution under mild conditions affords excellent yields of the 1, x ‐bis‐{(2‐aminobenzoyl‐)amino}alkanes ( 2a‐k ), which have been characterized by IR and NMR spectroscopy, high resolution mass spectrometry and elemental analysis. Diazotization of the bis‐{(2‐aminobenzoyl‐)‐amino}alkanes in aqueous solution gives high yields of the 1, x ‐bis‐(4‐oxo‐3,4‐dihydro‐1,2,3‐benzotriazin‐3‐yl)alkanes ( 1a‐k ), whch have also been characterized by IR and NMR spectroscopy, high resolution mass spectrometry and elemental analysis. The alkanediamines employed are as follows: ethylene diamine, 1,3‐propanediamine, 1,2‐propanediamine, 2‐methyl‐1,2‐propanediamine, 2,2‐dimethyl‐1,3‐propanediamine, 2‐hydroxy‐1,3‐propanediamine, 1,4‐diaminobutane, 1,5‐diaminopentane, 1,3‐diaminopentane ( DYTEK ® EP diamine ), 1,6‐diaminohexane and 1,7‐diaminoheptane. The alternative method of synthesis of the bis‐(4‐oxo‐3,4‐dihydro‐1,2,3‐benzotriazin‐3‐yl)alkanes ( 1 ) via the diazonium salt from methyl anthranilate was explored.