One air stable Cu(ii)-salen complex compound enables the generation of propargylamines. Mechanistic details, scope and limitations of this protocol are presented.

The hybrid bidentate 1‐(2‐pyridyl)benzotriazole (pyb) ligand was introduced into 3d transition metal catalysis. Specifically, [CuII(OTf)2(pyb)2]⋅2 CH3CN (1) enables the synthesis of a wide range of propargylamines by the A3 coupling reaction at room temperature in the absence of additives. Experimental and high‐level theoretical calculations suggest that the bridging N atom of the ligand imposes exclusive trans coordination at Cu and allows ligand rotation, while the N atom of the pyridine group modulates charge distribution and flux, and thus orchestrates structural and electronic precatalyst control permitting alkyne binding with simultaneous activation of the C−H bond via a transient CuI species.

Abstract:We demonstrate for the first time the high efficacy of tetranuclear Zn II 2 Ln III 2 coordination clusters (CCs) as catalysts for the Friedel-Crafts (FC) alkylation of indoles with a range of trans-β-nitrostyrenes. The reaction proceeds in good to excellent yields (76%-99%) at room temperature with catalyst loadings as low as 1.0 mol %.

Solventfree synthesis and key intermediate isolation in Ni2Dy2 catalyst development in the domino ringopening electrocyclization reaction of furfural and amines Article (Accepted Version) http://sro.sussex.ac.uk