A novel synthesis of 2-substituted oxazolines

Thermal rearrangement of N-acyl-2-oxazolidones in the presence of calcium oxide has been shown to provide a new entry into 2-substituted oxazolines.     

A novel one-pot synthesis of 2-arylpyrazoloquinolinone derivatives

Two regioisomers of 2-arylpyrazolo[3,4-c]quinolin-4(5H)-ones and 2-arylpyrazolo[4,3-c]quinolin-4(5H)-ones were synthesized by utilizing 3-arylsydnones, ethyl 3-bromopropynoate, and 2-aminophenylboronic acid pinacol ester in presence of catalytic agent Pd(PPh₃)₄. This efficient one-pot synthesis methodology involved 1,3-dipolar cycloaddition, Suzuki coupling reaction, and intramolecular cyclization three sequence steps.     

A novel one-pot synthesis of 2-benzoylpyrroles from benzaldehydes

We herein report a novel one-pot reaction for benzoylation of pyrrole. The key step in the reaction is generation of di(1H-pyrrol-1-yl)zirconium(IV) chloride complex which reacts with benzaldehydes and methyl benzoates to give 2-benzoylpyrroles as the major product.     

A novel synthesis of 2′-deoxy-α-disaccharides

Several 2′-deoxy-α-disaccharides were prepared in excellent yield using the imidate procedure recently introduced in our laboratory for the synthesis of 1,2-cis-disaccharides.     

A simple synthesis of novel 2-pyridones from chalcones

Several novel 2-pyridones were synthesized in good yields from a simple one-pot reaction by the condensation of different substituted chalcones and malonamide using sodium ethoxide in ethanol at room temperature. The structures of these 2-pyridones were elucidated from their ¹H, ¹³C and infrared spectral data as well as their elemental analysis. Different 2-pyridones tautomers were obtained as the solvent of crystallization changes.     

Cyanothioacetamide in heterocyclic synthesis : A novel synthesis of 2-pyridothione derivatives

Cyanothioacetamide (1) shows intermolecular cyclocondensation via refluxing in ethanolic sodium ethoxide solution to give a pyridothione derivative 5. Establishment of its structure as well as some of its chemical behaviour is discussed briefly.     

A novel synthesis of the carbapen-2-em derivatives

A new synthesis of the carbapen-2-em ring system, the basic nucleus of thienamycin and its relatives, is described.     

A novel method for the synthesis of 2-imidazolones

The superoxide ion electrochemically generated by reduction of oxygen, or chemically generated by dissolving potassium superoxide in ionic liquids, reacts with alkyl imidazolium cations of imidazolium-based ionic liquids at room temperature and atmospheric pressure to give the corresponding 2-imidazolones in excellent yields.     

A novel and practical synthesis of 2-benzoylbenzothiazoles and 2-benzylbenzothiazoles

A novel methodology for the synthesis of 2-benzoylbenzothiazoles and 2-benzylbenzothiazoles through FeCl₃·6H₂O catalyzed, air oxidized tandem process from commercially available 2-aminothiophenols and phenylacetaldehydes by using an ionic liquid as both reaction medium and co-catalyst was developed.     

A three-component novel synthesis of 1-carbamato-alkyl-2-naphthol derivatives

A new one-pot, efficient three-component condensation of benzaldehydes, 2-naphthol, and carbamates in the presence of silica supported sodium hydrogen sulfate as an effective heterogeneous catalyst for the synthesis of novel 1-carbamato-alkyl-2-naphthol derivatives under solvent-free conditions is described. The present methodology offers several advantages, such as high yields, short reaction times, and very easy workup.     

A novel synthesis of the carbapen-2-em ring system

A new synthesis of the carbapenem ring system, as found in thienamycin and related natural products, has been developed. The key step involves a highly efficient carbene insertion reaction which produces the bicyclic ring system by forming the N3 bond.     

A facile synthesis of novel 1,4-benzoxazepin-2-one derivatives

An efficient and simple synthesis of 1,4-benzoxazepin-2-one derivatives has been achieved via the reaction of isoquinoline, activated acetylenes, and 1-(6-hydroxy-2-isopropenyl-1-benzofuran-yl)-1-ethanone in water without using any catalyst. This one-pot reaction occurs in high yields under mild conditions.     

A novel synthesis of 4-propyl-2H-1-benzopyran-2-ones

Reaction of 2-hydroxybutyrophenones1–5 with ethoxycarbonylmethylenetriphenylphosphorane furnishes the 4-propyl-2H-1-benzopyran-2-ones6–10.

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Eine neue Synthese von 4-Propyl-2H-1-benzopyran-2-onen

Zusammenfassung Die Reaktion von 2-Hydroxybutyrophenonen1–5 ergab mit Ethoxycarbonylmethylentriphenylphosphoran die 4-Propyl-2H-1-benzopyran-2-one6–10

     

A novel improved synthesis of 3-aminopyrazine-2-carboxylic acid

A three step synthesis of 3-aminopyrazine-2-carboxylic acid ( 1 ) starting from pyrazine-2,3-dicarboxylic acid ( 5 ) is described. Diacid 5 is converted via the anhydride 6 into the ammonium salt of the half acid amide 7 which on Hofmann rearrangement gives the title compound in 55% overall yield.     

A novel pyrrole synthesis

The silver(I)-promoted oxidative cyclization of homopropargylamines at room temperature provides a novel access to pyrroles. Homopropargylamines are readily available by the addition of a propargyl Grignard reagent to Schiff bases.     

A novel synthesis of Aporhoeadanes

A one-pot synthesis of aporhoeadanes from the reaction of 3,4-dihydro-isoquinolines, 2-chloromethylbenzoyl chloride and sodium hydroxide, is described.