Syntheses of Some 3‐[1′ (1′ H )‐Substituent‐pyrazol‐5′‐yl] benzo [5,6]coumarins

3‐[1′ (1′ H )‐Substituent‐pyrazol‐5′‐yl] benzo [5,6] coumarins and 3‐(1′,2′‐oxazol‐5′‐yl)benzo[5,6]coumarin were prepared via condensation of 3‐(2′‐formyl‐1′‐chlorovinyl) benzo [5,6] coumarin with hydrazine derivatives or hydroxylamine. Reaction of 3‐[1′(1′ H )‐pyrazol‐5′‐yl] benzo [5,6] coumarin with alkyl halides, olefinic compounds or acid chlorides are described.