Transformations of Dialkyl Acetone-1,3-dicarboxylates via Their Dimethylaminomethylidene Derivatives Into 1-substituted 4-ethoxycarbonyl- 5-(ethoxycarbonylmethyl)pyrazoles, 7-amino- 2-ethoxycarbonyl-1H, 2H-pyrazolo[2,3-c]pyrimidin- 5-one, 4-hydroxypyridin-2(1H)-ones and 6-substituted 3-benzoylamino-2,5-dioxo-5,6- dihydro-2H-pyrano[3,2-c]pyridine- 8-carboxylates.
Silvo Zupančič, Jurij Svete and Branko Stanovnik*
* Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, P. O. box 537, 1000 Ljubljana, Slovenia * Corresponding author: E-mail: email@example.com
Diethyl 1-dimethylamino-3-oxobut-1-ene-2,4-dicarboxylate (2a), prepared from diethyl acetone-1,3-dicarboxylate and N,N-dimethylformamide dimethylacetal (DMFDMA), was transformed with hydrazines 3a-g into 1-susbtituted 4-ethoxycarbonyl- 5-(ethoxycarbonylmethyl)pyrazoles 5a-g, with aminoguanidine (6) into 7-amino-2-ethoxycarbonyl- 1H,2H-pyrazolo[2,3-c]pyrimidin-5-one (9), and with amines 10a-k into 4-hydroxypyridin-2(1H)-ones 11a-k. Compounds 11 were treated with methyl (Z)-2-benzoylamino-3-dimethylaminopropenoate (12) to give 6-substituted 3-benzoylamino- 2,5-dioxo-5,6-dihydro-2H-pyrano[3,2-c]pyridine-8-carboxylates 14, while in the reaction with methyl 3-dimethylamino- 2-(methoxycarbonyl)propenoate (15) decarboxylation of one of the ester groups took place producing alkyl (E)-1-alkyl-4-hydroxy-5-(3-methoxy-3-oxoprop-1-enyl)-6-oxo-1,6-dihydropyridine-3-carboxylates 17.
Keywords: 1-substituted 4-ethoxycarbonyl-5-(ethoxycarbonylmethyl)pyrazoles, 1H,2H-pyrazolo[2,3-c]pyrimidin-5- one, 4-hydroxypyridin-2(1H)-ones, 6-substituted 2H-pyrano[3,2-c]pyridine-8-carboxylates.