Copper( i ) and silver( i ) chemistry of vinyltrifluoroborate supported by a bis(pyrazolyl)methane ligand
Copper( i ) and silver( i ) chemistry of vinyltrifluoroborate supported by a bis(pyrazolyl)methane ligand
复制标题
双(吡唑基)甲烷配体负载的乙烯基三氟硼酸盐的铜( i ) 和银( i ) 化学
DOI：
10.1039/d1dt00974e
复制
发表时间：
2021
影响因子：
4
通讯作者：
Dias, H. V.
中科院分区：
文献类型：
--
作者：
Zacharias, Adway O.;Mao, James X.;Nam, Kwangho;Dias, H. V.
尽管不饱和有机三氟硼酸盐是金属有机化学中常见的合成子，但它们的过渡金属配合物很少受到关注。 [CH2(3,5-(CH3)2Pz)2]Cu(CH2CHBF3)、(SIPr)Cu(MeCN)(CH2CHBF3) 和 [CH2(3,5-(CH3)2Pz)2]Ag(CH2CHBF3) 代表稀有的可分离分子，其特征是造币金属上具有乙烯基三氟硼酸盐配体。 X 射线晶体结构显示这些配合物中存在三配位金属位点。乙烯基三氟硼酸酯基团以相对较近的 M-C(H)2 距离不对称地结合到 [CH2(3,5-(CH3)2Pz)2]M(CH2CHBF3) (M = Cu, Ag) 中的金属位点。然而，[CH2(3,5-(CH3)2Pz)2]M(CH2CHBF3) 和 M(CH2CHBF3) 的计算结构的 M–C(H)BF3 距离比 M–C(H)2 更短。这些分子具有各种涉及 BF3 基团氟的分子间或分子内接触，可能会影响这些 M-C 距离。在存在和不存在支持配体 CH2(3,5-(CH3)2Pz)2 的情况下，[CH2CHBF3]− 与 Cu+、Ag+ 和 Au+ 的结合能已在 wB97XD/def2-TZVP 理论水平上计算。计算表明，无论是否存在支持配体，Au+ 与 [CH2CHBF3]− 配体的结合最强，其次是 Cu+ 和 Ag+。然而，在所有三种金属中，支持配体削弱了烯烃与金属的结合。通过分析金属碎片与 [CH2CHBF3]− 的 π 和 π* 轨道之间的 σ 供体和 π 背键相互作用也发现了相同的趋势。
Although unsaturated organotrifluoroborates are common synthons in metal–organic chemistry, their transition metal complexes have received little attention. [CH2(3,5-(CH3)2Pz)2]Cu(CH2CHBF3), (SIPr)Cu(MeCN)(CH2CHBF3) and [CH2(3,5-(CH3)2Pz)2]Ag(CH2CHBF3) represent rare, isolable molecules featuring a vinyltrifluoroborate ligand on coinage metals. The X-ray crystal structures show the presence of three-coordinate metal sites in these complexes. The vinyltrifluoroborate group binds asymmetrically to the metal site in [CH2(3,5-(CH3)2Pz)2]M(CH2CHBF3) (M = Cu, Ag) with relatively closer M–C(H)2 distances. The computed structures of [CH2(3,5-(CH3)2Pz)2]M(CH2CHBF3) and M(CH2CHBF3), however, have shorter M–C(H)BF3 distances than M–C(H)2. These molecules feature various inter- or intra-molecular contacts involving fluorine of the BF3 group, possibly affecting these M–C distances. The binding energies of [CH2CHBF3]− to Cu+, Ag+ and Au+ have been calculated at the wB97XD/def2-TZVP level of theory, in the presence and absence of the supporting ligand CH2(3,5-(CH3)2Pz)2. The calculation shows that Au+ has the strongest binding to the [CH2CHBF3]− ligand, followed by Cu+ and Ag+, irrespective of the presence of the supporting ligand. However, in all three metals, the supporting ligand weakens the binding of olefin to the metal. The same trends were also found from the analysis of the σ-donation and π-backbonding interactions between the metal fragment and the π and π* orbitals of [CH2CHBF3]−.