Abstract

A novel tetrameric copper(I) complex containing tert-butyldiallylphosphine ligands, [CuCl{Bu-t-P (CH2CH = CH2)(2)}](4) (2), has been synthesized and characterized by structural and spectroscopic methods. X-ray diffraction analysis showed that 2 has a cubane-like solid structure of formula [CuCl{kappa(1)(P)-Bu-t-P (CH2CH = CH2)(2)}](4). In solution, a dynamic behavior generated by the cubane' - chair isomerization was detected by variable temperature NMR analysis. DFT calculations have been performed to explain the observed dynamic equilibrium in solution. The use of copper(I) complex 2 as catalyst for the synthesis of propargylamines via A(3)-coupling reactions has been tested. Complex 2 is capable of promoting A3-coupling reactions of both aromatic and aliphatic aldehydes with cyclic secondary amines and phenylacetylene. The reaction proceeds under mild condition and absence of solvent. (C) 2017 Elsevier B.V. All rights reserved.