3-Aminoisocarbostyril derivatives were synthesized in order to investigate their fluorescent properties. 5-Methoxy-, 6-methoxy-, 5, 6-dimethoxy-, 5-chloro-, and 6-chlorophthalides (Ia-Ie) reacted with potassium cyanide to give the corresponding (2-cyanomethyl) benzoic acids (IIa-IIe). Methyl (2-cyanomethyl) benzoates (IIIa-IIIe) were treated with aqueous amines under mild conditions to yield 3-aminoisocarbostyril derivatives having methoxy or chloro groups at the 6- and/or 7-positions. Reactions of IIIa-IIIe with 28% ammonia solution at 70-80°gave 3-aminoisocarbostyrils (IVa-IVe), and with 40% methylamine solution at room temperature gave 3-amino-2-methylisocarbostyrils (Va-Ve). IIIa-IIIe were allowed to stand with hydrazine hydrate at room temperature to give 2, 3-diaminoisocarbostyrils (VIa-VIe) in good yield, whereas IIIa-IIIe as well as VIa-VIe were heated with hydrazine hydrate in a water bath to yield 2-amino-3-hydrazinoisocarbostyril derivatives (VIIa-VIIe).
