A general method for the synthesis of 1,3,5-trisubstituted 1,2,4-triazoles has been developed from reaction of carboxylic acids, primary amidines, and monosubstituted hydrazines. This highly regioselective and one-pot process provides rapid access to highly diverse triazoles.

Nitroalkenes readily undergo palladium-catalyzed [3+2] cycloaddition with trimethylenemethane to generate nitrocyclopentanes in excellent yield and enantioselectivity. Furthermore, the products thus formed are highly versatile synthetic intermediates and provide convenient access to both cyclopentylamines and cyclopentenones.

The chemoselective functionalization of a range of dihaloaromatics with methyl, cyclopropyl, and higher alkyl Grignard reagents via iron-catalyzed cross-coupling is described. The site selectivity of C-X (X = halogen) activation is determined by factors such as the position of the halogen on the ring, the solvent, and the nucleophile. A one-pot protocol for the chemoselective synthesis of mixed dialkyl heterocycles is achieved solely employing iron catalysis.

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Dihaloaromatics. -Iron catalyzed coupling of dihaloarenes with alkyl Grignard reagents proceeds with high chemoselectivity to give monoalkylated and mixed dialkylated products. -(MALHOTRA*, S.; SENG, P. S.; KOENIG, S. G.; DEESE, A. J.; FORD, K. A.; Org. Lett. 15 (2013) 14, 3698-3701, http://dx.doi.org/10.1021/ol401508u ; Gentech Inc., South San Francisco, CA 94080, USA; Eng.) -Mais 50-171