Mononuclear Bis(imino)arylcopper(I) N-Heterocyclic Carbene Complex: Synthesis, Structure, and Reaction with Organic Azide

• Published in: European Journal of Inorganic Chemistry Vol. 2010; no. 28; pp. 4506 - 4512
• Main Authors: An, Dongli, Wang, Juanjuan, Dong, Ting, Yang, Ying, Wen, Tingbin, Zhu, Hongping, Lu, Xin, Wang, Ye
• Format: Book Review Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.10.2010; WILEY‐VCH Verlag
• Subjects: Azides; Carbenes; Copper; Density functional calculations; Weak interactions
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/ejic.201000433

Mononuclear bis(imino)arylcopper(I) N‐heterocyclic carbene compound [(IPM)CuL] {1, L = 2,6‐(RN=CH)2‐4‐tBuC6H2, R = 2,6‐iPr2C6H3, IPM = C[N(iPr)CMe]2} has been synthesized, structurally characterized, and its reaction with 1‐adamantyl azide investigated. The reaction of a less bulky arylcopper(I) compound [(IPM)CuPh] with the azide was also studied. The formation of the corresponding products [(IPM)CuN(1‐ad)NN(L)] (2) and [(IPM)CuN(Ph)NN(1‐ad)] (3) (1‐ad = 1‐adamantyl) reveals an aryl group transfer (L in 2 and Ph in 3) reactivity pattern mediated at CuI with the support of the N‐heterocyclic carbene. However, a Cu–N1‐ad σ‐bond and a Cu···NL weak bond were observed in the structure of 2, significantly different to the bonding in 3 in which a Cu–NPh σ‐bond and a Cu···N1‐ad weak bond were indicated. This may suggest an initial NT (NT, terminal N atom of the azide) coordination of the azide at the Cu center followed by aryl group transfer to NT. Complex 2 may undergo further bond rearrangement of the Cu···N bonds within a pseudo‐CuN3 four‐membered ring as a result of the large bulk of the ligand L. A new mononuclear bis(imino)arylcopper(I) N‐heterocyclic carbene complex has been synthesized that exhibits two types of solid‐state structures. Its reaction with N3(1‐ad) has been investigated and revealed an aryl group transfer reactivity pattern mediated at the CuI center with the support of the N‐heterocyclic carbene.