Abstract An efficient cycloaddition reaction of trifluoroacetohydrazonoyl bromides with nitroolefins was developed, which regioselectively produced 3‐trifluoromethyl‐4‐substituted pyrazoles. The has the advantages mild conditions, good tolerance functional groups and simple operation.

Cycloaddition reaction between C30 and hula-I, 3-diene was studied within the Snimework of AM I (RHF)level. The reaction involving the double bond between two hexagons and a hexagon and a pentagon, as wellas the cycloaddition products followed by disrotatory ogs s electrocyclic ring openings were considered.Thermodynamics parameters and stability energy and innsation state are evaluated in thre...

Abstract A concise total synthesis of (+)-aphanorphine is described. The key features the strategy include a Pd-catalyzed intermolecular trimethylenemethane [3+2]-cycloaddition to form ring C and Co-catalyzed radical cyclization through hydrogen-atom transfer close B. was completed in six steps.

The first transannular [4 + 2] cycloaddition reactions of macrocyclic dicobalt hexacarbonyl-dienyne complexes were demonstrated. Complexes were conveniently prepared through palladium(II)-catalyzed intramolecular oxidative cyclization of bis(vinylboronate esters) followed by complexation with dicobalt octacarbonyl. Transannular [4 + 2] cycloaddition reactions of the complexes occurred at lower ...

A novel series of indole and quinoline tricarboxamides were synthesized using simple and efficient one-pot pseudo-five-component reactions of 2-formylindole or 2-chloro-3-formyl quinolines, isocyanides, amines, and Meldrum’s acid as a CH-acid in CH2Cl2 at room temperature. This conversion has been achieved via the construction of new bonds including two C-C bonds, two ...

Reaction of 2-thiocarbamoyl thiazolium salts with dimethyl acetylenedicarboxylate proceeded via a tandem [3+2] cycloaddition and a unprecedented ring transformation to produce functionalized thieno[2,3-b]pyrazine derivatives in good to excellent yields.

The cycloaddition of the von Leusen's reagent (p-tolylsulfonyl)methyl isocyanide (TosMIC) to alpha-aroylketene dithioacetals (AKDTAs) in the presence of sodium hydride in THF at rt resulted in a facile synthesis of the 4-aroyl-3-methylsulfanyl-2-tosylpyrroles 3 in good yield along with a minor amount of 4-[(4-methylphenyl)sulfonyl]-1-[(methylsulfanyl)methyl]-1H-imidazole 4. This study lead to t...