Tseng CK, Lee CR, Han CC, Shyu SG. Copper(I)-anilide complex [Na(phen)3][Cu(NPh2)2]: an intermediate in the copper-catalyzed N-arylation of N-phenylaniline.
Chemistry 2011;
17:2716-23. [PMID:
21271618 DOI:
10.1002/chem.201002661]
[Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Indexed: 11/08/2022]
Abstract
Complex [Na(phen)(3)][Cu(NPh(2) )(2)](2), containing a linear bis(N-phenylanilide)copper(I) anion and a distorted octahedral tris(1,10-phenanthroline)sodium counter cation, has been isolated from the catalytic C-N cross-coupling reaction with the CuI/phen/tBuONa (phen=1,10-phenanthroline) catalytic system. Complex 2 can react with 4-iodotoluene to produce 4-methyl-N,N-diphenylaniline (3 a) with 70.6 % yield. In addition, 2 can work as an effective catalyst for C-N coupling under the same reaction conditions, thus indicating that 2 is the intermediate of the catalytic system. Both [Cu(NPh(2))(2)](-) and [Cu(NPh(2))I](-) have been observed by in situ electron ionization mass spectrometry (ESI-MS) under catalytic reaction conditions, thus confirming that they are intermediates in the reaction. A catalytic cycle has been proposed based on these observations. The molecular structure of 2 has been determined by single-crystal X-ray diffraction analysis.
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