R. Mekheimer, N. Mohamed, K. Sadek
Jul 15, 1997
Citations
0
Influential Citations
22
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
The reaction of 4-hydroxy-6-methyl-2-pyridone 1 with benzylidenemalononitriles in an ethanolic solution containing a catalytic amount of piperidine and α-cyanoacrylic esters in pyridine affords the corresponding 4H-pyrano[3,2-c]pyridines. However, it’s reaction with 3-(cyanomethylene)-2-indolinones gives either 2-amino-3-quinolinecarbonitriles or ethyl 2-amino-5′,6′-dihydro-7′-methyl-2,5′-dioxospiro-[indoline-3,4′-[4H]-pyrano[3,2-c]pyridine-3′-carboxylate. In contrast, the reaction of 1 with 3-aryl-2-cyano-2-propenethioamides affords 3,3′-benzylidenebis[4-hydroxy-6-methyl-2(1H)-3-pyridinone]s. The reaction of the obtained 4H-pyrano[3,2-c]pyridines with acetic anhydride affords the corresponding fused system.