Showing papers by "Branko Stanovnik published in 2010"
TL;DR: Microwave-assisted cycloaddition of (E)-3-dimethylamino-1-heteroaryl-prop-2-en-1ones to dimethyl acetylenedicarboxylates gives (2E,3E)-dimethyl-2-[(dimethyamino)methylene]-3-(substituted)succinates in 8-91% yield as mentioned in this paper.
37 citations
TL;DR: In this article, the usefulness of dialkyl acetone-1,3-dicarboxylates and their derivatives as versatile building blocks in the construction of many five and six-membered heterocyclic systems, and their fused analogs, is discussed.
Abstract: Publisher Summary This chapter illustrates the usefulness of dialkyl acetone-1,3-dicarboxylates and their (dimethylamino) methylidene derivatives as versatile building blocks in the construction of many five- and six-membered heterocyclic systems, and their fused analogs. It describes the synthesis of various hetrocyclic compounds using chemical reactions performed on dialkyl acetone-1,3-dicarboxylates and derivatives. The synthesized compounds include 1-substituted 4-ethoxycarbonyl-5-(ethoxycarbonylmethyl)pyrazoles; pyrazolo[4,3-c]pyridine derivatives; pyrazolo[4,3-d][1,2]diazepine derivatives; pyrazol-3-yl-pyrimidine derivatives and fused pyrazol-3-yl-pyranones; pyrazolo[1,5-c]pyrimidin-5-one derivatives; 7-amino-3-ethoxycarbonylpyrazolo[1,5-c]pyrimidin-5(1H)-one; pyridin-4(1H)ones; 4-hydroxypyridin-2(1H)-one and pyrano[3,2-c]pyridinone derivatives; thiazolo[5,4-c]pyridine derivatives; 4-oxo-1,4-dihydropyridazine-3,5-dicarboxylates; heteroaryl substituted pyrimidine derivatives; (pyrido[1,2-a]pyrimidin-3-yl)thiazole-5-carboxylates; and parallel solution-phase synthesis of 1,4-dihydropyridine derivatives.
11 citations
TL;DR: In this paper, the triazafulvalene system was used to obtain derivatives of triazefvalene systems with aromatic or hetero-aromatic amines by cycloaddition of (5Z)-5]-(dimethylamino)methylene]-3methylimidazolidine-2,4-dione.
10 citations
TL;DR: Substrates (I) undergo a microwave-promoted cycloaddition with DMAD to give cyclobutene intermediates which afford the desired functionalized 1,3-dienones after ring opening as discussed by the authors.
Abstract: Substrates (I) undergo a microwave-promoted cycloaddition with DMAD to give cyclobutene intermediates which afford the desired functionalized 1,3-dienones after ring opening.
3 citations
TL;DR: In this paper, the triazafulvalene system was used to obtain derivatives of triazefvalene systems with aromatic or hetero-aromatic amines by cycloaddition of (5Z)-5]-(dimethylamino)methylene]-3methylimidazolidine-2,4-dione.
Abstract: (2E,3Z)-2-(1-Methyl-2,5-dioxoimidazolidin-4-ylidene)-3-[(arylamino- or heteroarylamino)methylene]succinate 5 obtained by [2+2] cycloaddition of (5Z)-5-[(dimethylamino)methylene]-3-methylimidazolidine-2,4-dione (1) and dimethyl acetylenedicarboxylate (2) followed by substitution of the dimethylamino group with aromatic or heteroaromatic amines, afforded by heating in ethanol in the presence of potassium hydroxide, potassium salts 6. Acidification of 6 with hydrochloric acid afforded mixtures of (E)- and (Z)-isomers of methyl 4-(2-hydroxy-1-methyl-5-oxo-1H-imidazol-4(5H)-ylidene)-5-oxo-1-phenyl-4,5-dihydro-1H-pyrrole-3-carboxylates. On the other hand, alkylation of compounds 6 with methyl iodide or benzyl bromide produced the corresponding methyl (E)-4-(2-methoxy- or 2-benzyloxy-1-methyl-5-oxo-1H-imidazol-4(5H)-ylidene)-5-oxo-1-phenyl-4,5-dihydro-1H-pyrrole-3-carboxylates 9, derivatives of a new triazafulvalene system.
2 citations
TL;DR: In this paper, a library of 12 N(4′)-substituted di-tert-butyl (2S,4E)-4-arylaminomethylidene-5-oxopyrrolidine-1,2-dicarboxylates 6/6′a-l were prepared in 47 - 90 % yield by parallel acid-catalysed treatment of di-TERT-butyyl ( 2S, 4E)- 4-[dimethylamino)methylidene]-5-oxideopyrylidine-
Abstract: A library of twelve N(4′)-substituted di-tert-butyl (2S,4E)-4-arylaminomethylidene-5-oxopyrrolidine-1,2-dicarboxylates 6/6′a – l were prepared in 47 – 90 % yield by parallel acid-catalysed treatment of di-tert-butyl (2S,4E)-4-[(dimethylamino)methylidene]-5-oxopyrrolidine-1,2-dicarboxylate (4) with anilines 5a – j, ethyl glycinate (5k), and ethyl β -alaninate (3l). Acidolytic deprotection of compounds 6a – c, e – j afforded the corresponding (2S,4E)-4-arylaminomethylidene-5-oxopyrrolidine-2-carboxylic acids 7a – c, e – j in 39 – 99 % yield. The configuration around the C=C double bond in the enaminones 6 and 7 was determined by NMR spectroscopy.
1 citations
TL;DR: In this article, the transformations of imidazolidinedione derivatives (I and (VIII) with dicarbonyl compounds like (II) and (IX) into pyrano[2,3-d]pyrimidine (V) and chromene (X) derivatives are described.
Abstract: The transformations of imidazolidinedione derivatives (I) and (VIII) with dicarbonyl compounds like (II) and (IX) into pyrano[2,3-d]pyrimidine (V) and chromene (X) derivatives are described.
1 citations
TL;DR: In this paper, the usefulness of dialkyl acetone-1,3-dicarboxylates and their derivatives as versatile building blocks in the construction of many five and six-membered heterocyclic systems, and their fused analogs, is discussed.
Abstract: Publisher Summary This chapter illustrates the usefulness of dialkyl acetone-1,3-dicarboxylates and their (dimethylamino) methylidene derivatives as versatile building blocks in the construction of many five- and six-membered heterocyclic systems, and their fused analogs. It describes the synthesis of various hetrocyclic compounds using chemical reactions performed on dialkyl acetone-1,3-dicarboxylates and derivatives. The synthesized compounds include 1-substituted 4-ethoxycarbonyl-5-(ethoxycarbonylmethyl)pyrazoles; pyrazolo[4,3-c]pyridine derivatives; pyrazolo[4,3-d][1,2]diazepine derivatives; pyrazol-3-yl-pyrimidine derivatives and fused pyrazol-3-yl-pyranones; pyrazolo[1,5-c]pyrimidin-5-one derivatives; 7-amino-3-ethoxycarbonylpyrazolo[1,5-c]pyrimidin-5(1H)-one; pyridin-4(1H)ones; 4-hydroxypyridin-2(1H)-one and pyrano[3,2-c]pyridinone derivatives; thiazolo[5,4-c]pyridine derivatives; 4-oxo-1,4-dihydropyridazine-3,5-dicarboxylates; heteroaryl substituted pyrimidine derivatives; (pyrido[1,2-a]pyrimidin-3-yl)thiazole-5-carboxylates; and parallel solution-phase synthesis of 1,4-dihydropyridine derivatives.
1 citations
TL;DR: In this article, a library of 12 N(4′)-substituted di-tert-butyl (2S,4E)-4-arylaminomethylidene-5-oxopyrrolidine-1,2-dicarboxylates 6/6′a-l were prepared in 47 - 90 % yield by parallel acid-catalysed treatment of di-TERT-butyyl ( 2S, 4E)- 4-[dimethylamino)methylidene]-5-oxideopyrylidine-
Abstract: A library of twelve N(4′)-substituted di-tert-butyl (2S,4E)-4-arylaminomethylidene-5-oxopyrrolidine-1,2-dicarboxylates 6/6′a – l were prepared in 47 – 90 % yield by parallel acid-catalysed treatment of di-tert-butyl (2S,4E)-4-[(dimethylamino)methylidene]-5-oxopyrrolidine-1,2-dicarboxylate (4) with anilines 5a – j, ethyl glycinate (5k), and ethyl β -alaninate (3l). Acidolytic deprotection of compounds 6a – c, e – j afforded the corresponding (2S,4E)-4-arylaminomethylidene-5-oxopyrrolidine-2-carboxylic acids 7a – c, e – j in 39 – 99 % yield. The configuration around the C=C double bond in the enaminones 6 and 7 was determined by NMR spectroscopy.