Riethmann Melanie, Föhrenbacher Steffen A, Luz Christian, Ignat'ev Nikolai V, Finze Maik, Radius Udo
Institute of Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität, Würzburg, Am Hubland, 97074 Würzburg, Germany.
Dalton Trans. 2025 Jun 10;54(23):9310-9328. doi: 10.1039/d5dt00904a.
The synthesis and structural characterization of a variety of N-heterocyclic carbene (NHC)- and cyclic (alkyl)(amino)carbene (cAAC)-ligated cationic copper(I) complexes, featuring the weakly coordinating tris(pentafluoroethyl)trifluorophosphate counteranion (FAP- anion, [(CF)PF]) are reported. Starting with the complex [(IDipp)Cu(CMe)]FAP- (IIa) reported previously, (S. A. Föhrenbacher, M. J. Krahfuss, L. Zapf, A. Friedrich, N. V. Ignat'ev, M. Finze and U. Radius, - , 2021, , 3504-3516) a series of mononuclear complexes [(IDipp)Cu(LB)]FAP- (IDipp = 1,3-bis(2,6-di--propylphenyl)-imidazolin-2-ylidene) were obtained ligand exchange of CMe with neutral two valence electron (2 VE) donor molecules (LB = NH, 1; CHN = DABCO, 2; CHN = DMAP, 3; CHN = pyrazine, 4; CHN = acridine, 5; η-OCHN = acridone, 6; CHS = SEt, 7; CHS = THT, 8; PCy, 9), alongside the dinuclear species [{(IDipp)Cu}(CNH)]2FAP- (10) with 1,2,4-triazole. In a parallel strategy, [(cAAC)Cu(CMe)]FAP- (IIb) was employed as precursor for Cu(I) complex formation, leading to [(cAAC)Cu(LB)]FAP- (LB = CHN, 13; CHS, 14) and the dinuclear complexes [{(cAAC)Cu}(CHN)]2FAP- (11) and [{(cAAC)Cu}(CHN)]2FAP- (12). Additionally, the reaction of [(carbene)CuF] with (CF)PF in the presence of different 2 VE donor ligands induced fluoride replacement with a 2 VE donor ligand (LB). This strategy facilitated the isolation of a broad range of complexes of the type [(carbene)Cu(LB)]FAP, including [(IDipp)Cu(LB)]FAP- (LB = (NCMe), 16; NCPh, 17; NHPh, 18; NHPh, 21; NCH, 22; NCHF, 24; NCHF, 25; η-OCPh, 27), [(SIDipp)Cu(NHPh)]FAP- (19) (SIDipp = 1,3-bis(2,6-di--propylphenyl)-imidazolidin-2-ylidene) and [(cAAC)Cu(LB)]FAP- (cAAC = 1-(2,6-di--propylphenyl)-3,3,5,5-tetramethyl-pyrrolidin-2-ylidene; LB = NCMe, 15; NHPh, 20; NCH, 23; THF, 28). Additionally, the dinuclear complex [{(IDipp)Cu(μ-ONCH)}]2FAP- (26) was obtained upon reaction with pyridine--oxide. In all cases the carbene ligand stayed intact and the formation of Lewis acid/base pairs of the 2 VE ligand and (CF)PF was never observed. As a result, mixtures of [(carbene)CuF] and (CF)PF may serve as synthons for [(carbene)Cu], as demonstrated in this work.
报道了多种N-杂环卡宾（NHC）和环状（烷基）（氨基）卡宾（cAAC）配位的阳离子铜（I）配合物的合成及结构表征，其具有弱配位的三（五氟乙基）三氟磷酸根抗衡阴离子（FAP-阴离子，[(CF)PF]）。从先前报道的配合物[(IDipp)Cu(CMe)]FAP-（IIa）（S. A. Föhrenbacher，M. J. Krahfuss，L. Zapf，A. Friedrich，N. V. Ignat'ev，M. Finze和U. Radius， - ，2021， ，3504 - 3516）出发，通过CMe与中性二价电子（2 VE）供体分子（LB = NH，1；CHN = DABCO，2；CHN = DMAP，3；CHN = 吡嗪，4；CHN = 吖啶，5；η-OCHN = 吖啶酮，6；CHS = SEt，7；CHS = THT，8；PCy，9）进行配体交换，得到了一系列单核配合物[(IDipp)Cu(LB)]FAP-（IDipp = 1,3 - 双（2,6 - 二 - 丙基苯基） - 咪唑啉 - 2 - 亚基），以及与1,2,4 - 三唑形成的双核物种[{(IDipp)Cu}(CNH)]2FAP-（10）。在平行策略中，[(cAAC)Cu(CMe)]FAP-（IIb）被用作形成Cu（I）配合物的前体，得到[(cAAC)Cu(LB)]FAP-（LB = CHN，13；CHS，14）以及双核配合物[{(cAAC)Cu}(CHN)]2FAP-（11）和[{(cAAC)Cu}(CHN)]2FAP-（12）。此外，[(卡宾)CuF]与(CF)PF在不同的2 VE供体配体存在下反应，导致氟被2 VE供体配体（LB）取代。该策略有助于分离出多种类型为[(卡宾)Cu(LB)]FAP的配合物，包括[(IDipp)Cu(LB)]FAP-（LB = (NCMe)，16；NCPh，17；NHPh，18；NHPh，21；NCH，22；NCHF，24；NCHF，25；η-OCPh，27），[(SIDipp)Cu(NHPh)]FAP-（19）（SIDipp = 1,3 - 双（2,6 - 二 - 丙基苯基） - 咪唑烷 - 2 - 亚基）和[(cAAC)Cu(LB)]FAP-（cAAC = 1 - （2,6 - 二 - 丙基苯基） - 3,3,5,5 - 四甲基 - 吡咯烷 - 2 - 亚基；LB = NCMe，15；NHPh，20；NCH，23；THF，28）。此外，与吡啶 - N - 氧化物反应得到双核配合物[{(IDipp)Cu(μ - ONCH)}]2FAP-（26）。在所有情况下，卡宾配体保持完整，从未观察到2 VE配体与(CF)PF形成路易斯酸/碱对。结果表明，[(卡宾)CuF]和(CF)PF的混合物可作为[(卡宾)Cu]的合成子，如本工作所示。
