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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 MOtBu (M = Li, Na, K) proved successful only for M = Li to afford the spectroscopically characterized ate product [(6-MesDAC)CuCl·LiOtBu·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., Treatment of CuCl with the diamidocarbene 6-MesDAC generated [(6-MesDAC)CuCl]2, [(6-MesDAC)2(CuCl)3], and [(6-MesDAC)2(CuCl)4]. Efforts to convert the dimer to a Cu−OtBu complex led instead to a partially metathesized ate complex; attempts at crystallization afforded instead a 1:1 mixture of [(6-MesDAC)CuCl]2 and [(6-MesDAC)CuCl].