Search

The selective construction of a diverse array of five-membered aromatic heterocycles from common starting materials is an attractive and challenging task. We report here that 5-alkylthio-pyrroles, 4-alkylthiocarbonyl-pyrroles and 2-alkylthio-4-tosyl-furans can be prepared, selectively, in a single operation using the readily available α-formyl ketene dithioacetals as common precursors, through their regiodivergent heterocyclization with α-acidic isocyanides controlled by the choice of suitable catalysts/promoters. [ABSTRACT FROM AUTHOR]

A tandem formal [3+2] cycloaddition/cyclization reaction of aminochalcones with tosylmethyl isocyanide derivatives was developed for the practical and convenient synthesis of diverse tricyclic pyrrolo[3,4- c]quinolines in high to excellent yields. In this domino process, three new bonds and two rings are successively formed at ambient conditions. [ABSTRACT FROM AUTHOR]

α-Acidic isocyanidesare versatile reagents in organicsynthesis, especially for the synthesis of five-membered heterocyclesvia [3 + 2]-cycloaddition reactions with activated multiplebonds. In this communication, the first [3 + 3]-cross-cycloadditionof α-acidic isocyanides with 1,3-dipolar azomethine iminesto generate a series of 1,2,4-triazine derivatives with significantregiochemical control under mild catalytic reaction conditionsis described. This new strategy shows that α-acidic isocyanidescan also be taken as potent reagents for the synthesis of six-memberedheterocycles through [3 + 3]-cross-cycloaddition reactionswith 1,3-dipoles. [ABSTRACT FROM AUTHOR]

The article presents a chemical reaction of direct synthesis of the pyrrole [3,4-c] quinolines by using the domino reaction of tosylmethyl isocyanides and aminochalcones.

A base-catalyzed tandem Michael addition/intramolecular isocyanide [3 + 2] cycloaddition of ethyl isocyanoacetate and Michael acceptors with tethered carbonyl groups is described. This reaction leads to the formation of fused oxazolines in a highly diastereoselective manner under very mild conditions. [ABSTRACT FROM AUTHOR]

An abstract of the article "[3 + 3]-Cycloaddition Reactions of α-Acidic Isocyanides with 1,3-Dipolar Azomethine Imines" is presented.

The base-promoted reaction of cyclic enediones with isocyanides (II) leads to 7- and 8-membered-ring fused pyrroles (III) in moderate yields. [ABSTRACT FROM AUTHOR]