Using 1,2-Dicarboxybenzenes Phthalic Acids as Substrates

Such substrates furnish l,4(2//,3//)-phthalazinediones, as illustrated in the following examples. 

Phthalic acid (101) with A-(l,2-diphenylethylidene)-A -methylhydrazine gave 2-methyl-3-(a-phenylstyryl)-l,4(27/,3/f)-phthalazinedione (102) (neat PCI3, 20°C, 8h 68%) a dozen analogs likewise.  

Using l,2-Bis(chloroformyl)benzenes (Phthaloyl Chlorides) as Substrates 

---