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Synthesis and chemical transformations of 2,3-dihydropyrrole-2,3-diones annelated on the [a] side by azaheterocycles. (Review)

“…The reaction of the N-substituted amide 3 with one mole of oxalyl chloride leads to the product from dehydration and closure of the 1,3-dioxazine ring, i.e., the enamine 4, which is acylated by a second molecule of oxalyl chloride with the formation of a derivative of pyrrolo[2,1-b][1,3]oxazinetrione 5 [21]. + -During treatment with oxalyl chloride 1-chloromethyl-and 1-methyl-6,7-dimethoxy-3,4,6,7-tetrahydroisoquinolines 6 [14], the substituted tetrahydro derivatives 7 of isoquinolines (n = 1) [7, 9, 11, 17-19, 22, 23] and 5H-benzo[c]azepines (n = 2) [24][25][26][27], the cyclohexaannelated tetrahydroisoquinolines 8 [28] and the dihydroisoquinolines 9 [16], and tetrahydrofuro [3,2-c]pyridine [29] form the corresponding 2,3-dihydro-2,3-pyrrolediones annelated with the azaheterocycles on the [a] side with good yields (57-82% …”

Five-membered 2,3-dioxo heterocycles: LXXVII. [4 + 2]-Cycloaddition of alkyl vinyl ethers to 3-aroylpyrrolo[2,1-c][1,4]benzoxazine-1,2,4(4H)-triones

“…IR spectrum, ν, cm -1 : 1786 (C 2 =O), 1724 (C 11 =O, C 12 =O). 1 H NMR spectrum, δ, ppm: VIa: 1.11 t (3H, CH3 , J = 7.0 Hz), 2.39 m (2H, 17-H), 3.72 m and 3.82 m (2H, OCH 2 ), 5.79 m (1H, CH), 7.34-7.95 m (9H, H arom ); VIIa: 1.21 t (3H, CH 3 , J = 7.2 Hz), 2.19 m (1H, 17-H, J = 10.4, 12.8 Hz), 2.62 m (1H, 17-H, J = 4.2, 13.0 Hz), 3.82 m and 4.04 m (2H, OCH 2 ), 5.60 m (1H, CH, J = 4.0, 10.4 Hz), 7.34-7.85 m (9H, H arom ). 13 C NMR spectrum, δ C , ppm: VIa: 14.67 (Me), 38.88 (C 17 ), 54.48 (OCH 2 ), 65.65 (C 1 ), 100.33 (C 16 ), 102.86 (C 13 ), 116.68-143.10 (C arom ), 159.17 (C 11 ), 160.77 (C 2 ), 166.92 (C 14 ), 175.96 (C 12 ).…”

“…Thermal [4 + 2]-cycloaddition of polar C=C dienophiles at the conjugated C 5 =C 4 -C=O bond system of monocyclic 4-aroyl-substituted 1H-pyrrole-2,3-diones was reported to produce pyrano [4,3-b]pyrrole heterocyclic system [3][4][5]. Cycloaddition of olefins to 1H-pyrrole-2,3-diones fused to a 1,4-benzoxazin-2-one fragment, i.e., pyrrolo [2,1-c] [1,4]benzoxazine-1,2,4(4H)-triones, was not studied previously.…”

“…Cycloaddition at conjugated multiple bonds in 4-acyl-2,3-dihydro-1H-pyrrole-2,3-diones fused to an isoquinoline fragment was extensively studied with a view to develop a strategy for building up heterocyclic system typical of Erythrina alkaloids [2,3]. Thermal [4 + 2]-cycloaddition of polar C=C dienophiles at the conjugated C 5 =C 4 -C=O bond system of monocyclic 4-aroyl-substituted 1H-pyrrole-2,3-diones was reported to produce pyrano [4,3-b]pyrrole heterocyclic system [3][4][5].…”

Five-membered 2,3-dioxoheterocycles: LXXXIV. [4+2]-Cycloaddition of styrene to 4,5-diaroyl-1H-pyrrole-2,3-diones. Crystal and molecular structures of 7a-(2,5-dimethylbenzoyl)-4-(2,5-dimethylphenyl)-1-(4-methoxyphenyl)-6-phenyl-7,7a-dihydropyrano[4,3-b]-pyrrole-2,3(1H,6H)-dione

“…1H-Pyrrole-2,3-diones exhibited a considerable reactivity in the Diels-Alder reactions [2,3]. Polar olefi ns took part in the [4+2]-cycloaddition at the conjugated bonds system C 5 =C 4 -C=O of the 4-benzoyl-1-phenyl-5-ethoxycarbonyl-1H-pyrrole-2,3-dione that was applied to the building up of the heterocyclic system of pyrano [4,3-b]pyrrole [4,5].…”