K-10 effectively catalyzed the condensation and substitution reactions. The approach was based on the direct cyclization of phthalaldehydicacid and opianic acid with substituted hydrazines. The reactions provided excellent yields and high selectivities in very short time (5-35 minutes). phthalazinones - phthalaldehydicacid - opianic acid - hydrazines - montmorillonite K-10 - microwave heating