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Copper diamidocarbene complexes: characterization of monomeric to tetrameric species.

ABSTRACT: Treatment of CuCl with 1 equiv of the in situ prepared N-mesityl-substituted diamidocarbene 6-MesDAC produced a mixture of the dimeric and trimeric copper complexes [(6-MesDAC)CuCl]2 (1) and [(6-MesDAC)2(CuCl)3] (2). Combining CuCl with isolated, free 6-MesDAC in 1:1 and 3:2 ratios gave just 1 and 2, respectively, while increasing the ratio to >5:1 allowed the isolation of small amounts of the tetrameric copper complex [(6-MesDAC)2(CuCl)4] (3). Efforts to bring about metathesis reactions of 1 with MO(t)Bu (M = Li, Na, K) proved successful only for M = Li to afford the spectroscopically characterized ate product [(6-MesDAC)CuCl·LiO(t)Bu·2THF] (5). Attempts to crystallize this species instead gave a 1:1 mixture of 1 and the monomer [(6-MesDAC)CuCl] (6). The X-ray structures of 1-3 and 1 + 6, along with the cation [Cu(6-MesDAC)2](+) (4), have been determined.

SUBMITTER: Collins LR

PROVIDER: S-EPMC3989936 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Copper diamidocarbene complexes: characterization of monomeric to tetrameric species.

Collins Lee R LR Lowe John P JP Mahon Mary F MF Poulten Rebecca C RC Whittlesey Michael K MK

Inorganic chemistry 20140211 5

Treatment of CuCl with 1 equiv of the in situ prepared N-mesityl-substituted diamidocarbene 6-MesDAC produced a mixture of the dimeric and trimeric copper complexes [(6-MesDAC)CuCl]2 (1) and [(6-MesDAC)2(CuCl)3] (2). Combining CuCl with isolated, free 6-MesDAC in 1:1 and 3:2 ratios gave just 1 and 2, respectively, while increasing the ratio to >5:1 allowed the isolation of small amounts of the tetrameric copper complex [(6-MesDAC)2(CuCl)4] (3). Efforts to bring about metathesis reactions of 1 wi ...[more]

PMID: 24512071

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