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SINTESI CHEMO- E REGIOSELETTIVA DI PIRROLI E PIRAZOLI PER REAZIONE DI DIENI DI DANISHEFSKY CON 1,2-DIAZA-1,3-BUTADIENI
No full textNUOVA ED ELEGANTE SINTESI DI IMIDAZOLI DA ALFA-AZIRIDINOIDRAZONI VIA 1,5 ELETTROCICLIZZAZIONE DI AZAVINIL AZOMETIN ILIDI
No full textCopper(II)/Copper(I)-catalyzed aza-Michael addition/click reaction of in situ generated alpha-azidohydrazones: synthesis of novel pyrazolone-triazole framework
No full textA one-pot Cu(II)-catalyzed aza-Michael addition of trimethylsilyl azide to 1,2-diaza-1,3-dienes and Cu(I)-catalyzed 1,3-dipolar cycloaddition of in
situ generated alpha-azidohydrazones with alkynes is reported. This process combining two consecutive steps with recycling of the catalyst
(Cu(OAc)2·H2O) represents a useful protocol for the smooth synthesis of novel pyrazolone-triazole derivatives
Synthesis of Highly Functionalized 1,3-Oxathiazoles via an Unusual [4+1] Annulation alpha,alpha'-Dioxothione with 1,2-Diaza-1,3-dienes
No full textThe present method provides highly functionalized 1,3-oxathioles 4 through an unusual base-promoted [4+1] annulation between α,α’-dioxothione (DT) 2a, generated in situ from phthalimide precursor (DTPht) 1a and 1,2-diaza-1,3-dienes (DDs) 3. An intriguing scaffold 5 comprised of spiro-fused oxathiole and pyrazolone components was also obtained in moderate yield
SINTESI DI DERIVATI PIRIDAZINICI PER REAZIONE DI CLORO-AZOLACHENI CON COMPOSTI METILENICI ATTIVATI
No full textXXV CONVEGNO INTERREGIONALE TOSCANA UMBRIA MARCHE ABRUZZO SOCIETA' CHIMICA ITALIAN
Azavinyl Azomethine Ylides fromThermal Ring Opening ofr-Aziridinohydrazones: Unprecedented1,5-Electrocyclization to Imidazoles
No full textMichael-type addition of aziridinecarboxylates to 1,2-diaza-1,3-butadienes under solvent-free conditions (SFC) resulted in the formation of
alpha-aziridinohydrazone adducts. In toluene under reflux,alpha-aziridinohydrazones gave imidazoles in moderate to good yields. Such a reactivity
pattern is explained by 1,5-electrocyclization of azavinyl azomethine ylide generated through thermal ring opening of r-aziridinohydrazone
Synthesis of Densely Functionalized 3a,4-Dihydro‐1H‐Pyrrolo[1,2‐b]Pyrazoles via Base Mediated Domino Reaction of VinylMalononitrileswith 1,2-Diaza-1,3-dienes
Full text linkDomino reaction of vinyl malonitriles (VMs) with 1,2-diaza-1,3-dienes (DDs) produce unprecedented 3a,4-dihydro-1H-pyrrolo[1,2-b]pyrazole systems in chemo- regio- and stereoselective fashion. This base promoted (DIPEA) one-pot transformation involving multiple steps implicates the formation of one new C–C bond, two C–N bonds and two new fused heterocyclic rings with total atom econom
A DIVERSITY-ORIENTED STRATEGY FOR THE CONSTRUCTION OF PYRROLES AND PYRAZOLES THROUGH REACTIONS OF DANISHEFSKY'S DIENES WITH 1,2-DIAZA-1,3-BUTADIENES
No full textSynthesis of Tetrahydropyridazine Amino Acid Derivatives by a Formal [4+2| Cycloaddition Reaction of 1,2-Diaza-1,3-dienes with Dehydroalanine Esters
No full textA highly efficient formal inverse electron demand aza Diels–Alder reaction of 1,2-diaza-1,3-dienes (DDs) is accomplished using dehydroalanine esters (DhAs) as electron-rich dienophiles. Both diastereoisomers of unprecedented α,α-disubstituted cyclic tetrahydropyridazine amino acids were obtained in excellent yields, in refluxing acetonitrile without activation
SINTESI DI IMIDAZOLI VIA AZOMETN ILIDE PER REAZIONE DI 1,2-DIAZA-1,3-BUTADIENI CON AZIRIDINE
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