Chemical transformations on 6-aryl-3-cyano-4-methylthio-pyran-2( H )-ones: Synthetic and structural studies on novel N-phenylpyrazoles and N- phenylpyrazolylcoumarins

Seven 6-aryl-3-cyano-4-methylthiopyran-2(H)-ones 1-7 have been prepared and used for the efficient synthesis of twelve 1,3-diaryl-5-cyanomethylpyrazolcs 8-19, one 3-cyanomethyl-5-(3,4-methylenedioxyphenyl)pyrazole 22 and one 5-cyanomethyl-3-phenylisoxazole 23. Further, two 1,3-diaryl-5-cyanomethylpyrazoles 10 and 11 have been used for the preparation of three novel N-phenylpyrazolylcoumadns 24-26. Structures of 3-cyano-6-(3,4-methylenedioxyphenyl)-4-methlthiopyran-2(H)-one 7, 3-cyanomethyl-5-(3,4-methylenedioxyphenyl)pyrazole 22 and 5-cyanomethyl-3-phenylisoxazole 23 have been confirmed by their X-ray crystallographic studies.