1,720,972 research outputs found
Efficient synthesis of nitrogen heterocycles by cyclization of bis(nucleophiles) with oxaldiimidoyl dichlorides
No full textThe reaction of ambident dianions and bis-nucleophiles with oxaldiimidoyl dichlorides offers a new strategy for the regio- and diastereoselective synthesis of a variety of biologically relevant N-heterocycles. This includes cyclization, domino, one-pot, and double-anion-capture reactions
Regio- and diastereoselective synthesis of N-aryl-5-alkylidene-5H-pyrrol-2-ones by a new domino reaction of 1,3-dicarbonyl dianions with oxalic acid-bis(imidoyl)chlorides
No full textThe reaction of dilithiated dicarbonyl compounds with oxalic acid-bis(imidoyl)chlorides results in regio- and stereoselective formation of 5-(alkylidene)-5H-pyrrol-2-ones
Regio- and diastereoselective synthesis of N-aryl-5-alkylidene-5H-pyrrol-2-ones by a new domino reaction of 1,3-dicarbonyl dianions with oxalic acid-bis(imidoyl)chlorides
No full textThe reaction of dilithiated dicarbonyl compounds with oxalic acid-bis(imidoyl)chlorides results in regio- and stereoselective formation of 5-(alkylidene)-5H-pyrrol-2-ones
Efficient synthesis of nitrogen heterocycles by cyclization of bis(nucleophiles) with oxaldiimidoyl dichlorides
No full textThe reaction of ambident dianions and bis-nucleophiles with oxaldiimidoyl dichlorides offers a new strategy for the regio- and diastereoselective synthesis of a variety of biologically relevant N-heterocycles. This includes cyclization, domino, one-pot, and double-anion-capture reactions
One-pot synthesis of functionalized indoles by cyclization of lithiated amides and nitriles with oxaldiimidoyl dichlorides
No full textThe reaction of the dianion of phenylacetonitrile with substituted oxalic acid bis(imidoyl)chlorides resulted in the formation of 2-alkylidene-3-iminoindoles, containing substituents at different positions of the heterocyclic nucleus. The cyclization of lithiated amides with bis(imidoyl) chlorides afforded (3-imino-2,3-dihydro-1H-indol-2-ylidene) acetic amides. Excellent regio- and E-diastereoselectivities were observed in all reactions
Regioselective synthesis of heterospirocyclic isobenzofuranones and medium-sized lactones by multiple anion capture reactions of 1,3-dianions
No full textThe multicomponent reaction of 1,3-dianions with ketones and oxalic acid dichloride or diethylmalonic dichloride afforded six- to eight-membered lactones, Treatment of the dianion of 3-acetylindole with benzophenone and diethylmalonic dichloride resulted in the formation of a cyclic 1,3,5-triketooctene. The reaction of 1,3-dianions with ketones and phthalic dichloride resulted in the formation of heterospirocyclic isobenzofuranones rather than of medium-sized rings
New and efficient synthesis of pyrrolo[3,2-b]pyrrole-2,5-diones by double-anion-capture reactions of ester carbanions with bis(imidoyl)chlorides of oxalic acid
No full textA variety of pyrrolo[3,2-b]pyrrole-2,5-diones were efficiently prepared by a new domino-reaction of ester carbanions with oxalic acid-bis(imidoyl)chlorides. This reaction proceeded by condensation of 2 equiv of the ester with the bis(imidoyl)chloride and subsequent intramolecular attack of the nitrogen atoms of the bis-enamine intermediate onto the ester groups. The products, which can be regarded as dilactams of pentalene, represent useful synthetic pigments due to their optical features, their stability, and low solubility. The W-vis properties of the pyrrolo[3,2-b] pyrrole-2,5-diones could be efficiently controlled by the substituents attached to the heterocyclic core. The scope and the limitations of the new cyclization reaction were investigated
One-pot synthesis of functionalized indoles by cyclization of lithiated amides and nitriles with oxaldiimidoyl dichlorides
No full textThe reaction of the dianion of phenylacetonitrile with substituted oxalic acid bis(imidoyl)chlorides resulted in the formation of 2-alkylidene-3-iminoindoles, containing substituents at different positions of the heterocyclic nucleus. The cyclization of lithiated amides with bis(imidoyl) chlorides afforded (3-imino-2,3-dihydro-1H-indol-2-ylidene) acetic amides. Excellent regio- and E-diastereoselectivities were observed in all reactions
Synthesis and properties of dimetallic complexes based on a new oxalamidine-derived ligand system with pendant pyridine functionality
No full textReaction of sterically hindered bis(imidoyl)chlorides of oxalic acid with picolylamine afforded conformationally locked oxalic acid-derived amidines with pendant pyridine functionalities. Based on this new multivalent ligand system, dimetallic complexes were efficiently prepared
Stereoselective synthesis of 2-alkylidene-3-iminoindoles by reaction of 1,1-dianions with oxalic acid bis(imidoyl) chlorides
No full textTreatment of dilithiated nitriles and sulfones with oxalic acid bis(imidoyl) chlorides resulted in a new cyclization reaction which provided a variety of (3-imino-2,3-dihydro-1H-indol-2-ylidene)-acetonitriles and -sulfones in good yields. The reactions proceeded by condensation of the dianions with the first imidoyl chloride group of the bis(imidoyl) chloride, subsequent intramolecular attack of the ortho carbon of the arylimino group onto the second imidoyl chloride group, and final aromatization. Excellent stereoselectivities were observed in most cases
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