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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 series of tunable iminium ions, generated in situ by the condensation of 4-trifluoromethyl-p-quinols with cyclic amines, can lead to the divergent synthesis of trifluoromethylated arylamines in a single step via redox-neutral isomerization. The direct α- and β-functionalization of saturated amines can be achieved regioselectively under mild conditions. [ABSTRACT FROM AUTHOR]

A new three-component reaction, namely condensation–anti-Michael addition–aromatization, enabling the construction of benzylic compounds is disclosed. This reaction can not only act as an alternative approach to regioselective Csp2–H trifluoromethylation of arenes through an “aromatic to be” strategy, but also provides a simple, convenient, step-economic, and practical strategy for the in situ generation of electrophilic p-(trifluoromethyl)benzyl species under extremely mild conditions. [ABSTRACT FROM AUTHOR]

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]