CARBORANE COMPLEXES OF NICKEL AND PLATINUM - SYNTHESIS AND PROTONATION REACTIONS OF ANIONIC ALLYL(CARBORANE) SPECIES
CARBORANE COMPLEXES OF NICKEL AND PLATINUM - SYNTHESIS AND PROTONATION REACTIONS OF ANIONIC ALLYL(CARBORANE) SPECIES
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DOI：
10.1021/ic00086a017
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发表时间：
1994-04-13
影响因子：
4.6
通讯作者：
STONE, FGA
中科院分区：
文献类型：
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作者：
CARR, N;MULLICA, DF;STONE, FGA
Na2[nido-7,8-Me2-7,8-C2B9H9] 与 [Ni2(mu-Br)2(eta3-C3H5)2] 或 [Pt2(mu-Br)2(eta-C3H5)2] 在四氢呋喃中反应，得到阴离子物质 [M(eta3-C3H5)(eta 5-7,8-Me2-7,8-C2B9H9)]-（M = Ni 或 Pt），已作为其 [NEt4]+ 和 [N(PPh3)2]+ 盐 1a-1d 被分离。在合适的底物分子 (L = CO 或 CNBu(t)) 存在下，试剂 1 在低温下质子化 (HBF4.Et2O) 得到中性化合物 [ML2-(eta5-7,8-Me2-7,8-C2B9H9)] (2a, M = Ni, L = CO; 2b, M = Ni, L = CNBu(t); 2c, M = 铂，L = CO； 2d，M = Pt，L = CNBu(t))。二羰基镍配合物 2a 的二氯甲烷溶液通过一氧化碳的损失缓慢分解，得到异构二金属物质 [Ni2(CO)2(eta5-7,8-Me2-7,8-C2B9H9)2] (3a)， [Ni2(CO)2(eta5-7,8-Me2-7,8-C2B9H9)(eta5-2,7-Me2-2,7-C2B9H9)](3b)和[Ni2(CO)2(eta5-2,7-Me2-2,7-C2B9H9)2](3c)。通过X射线衍射建立了3c的分子结构，其中两个笼的碳硼烷CMe基团占据eta5-C2B9 nido笼的不同层的顶点。晶体为单斜晶系，空间群 C2/c（第 15 号），a = 21.498(5) 埃，b = 7.722(2) 埃，c = 14.962(3) 埃，β = 98.21(2) 度，Z = 4。每个镍原子由末端羰基和2,7-Me2-2,7-C2B9H9 碳硼烷笼，其协调的 CBBBB 环表现出明显的非平面性。此外，金属-金属矢量由两个三中心、两电子 B-H 半箭头组成，指向右侧 Ni 的“agostic”相互作用。 [N(PPh3)2][Pt(eta3-C3H5)(eta5-7,8-Me2-7,8-C2B9H9)]的CH2Cl2溶液(1d)用HBF4.Et2O在大约10℃下处理。 -78℃，然后添加炔烃 PhC=CH，得到二金属物质 [Pt2{mu-sigma,sigma':eta4-C(H)C(Ph)C(H)C(Ph)}(eta5-7,8-Me2-7,8-C2B9H9)2] (4)，其结构已通过 X 射线衍射确定。晶体为三斜晶系，空间群 P1BAR（No. 2），a = 13.317(2) 埃，b = 16.783(4) 埃，c = 17.289(4) 埃，α = 64.94(2(度，β = 83.31(2) 度，gamma = 78.58(2) 度，Z = 4. 二炔 分子以“头对尾”的方式偶联，产生桥接“C4”部分，该部分通过两个末端碳原子与其中一个金属中心 σ 键合，并与第二个金属中心 eta4 键合。此外，每个铂原子都通过以五键方式结合的 7,8-Me2-7,8-C2B9H9 碳硼烷笼连接，两者都没有 笼参与外多面体键合。 1a 在 CH2Cl2 中质子化 (HBF4.Et2O)，然后添加 [Co2(CO)8]，得到三核金属配合物 [Co2Ni(mu-CO)(CO)5(eta5-7,8-Me2-7,8-C2B9H9)] (5)，其中 NiC2B9 金属碳硼烷笼形成两个 外多面体 B-H 半箭头指向右 Co“失常”相互作用。除了 X 射线衍射研究之外，新化合物还通过微量分析、H-1、C-13 和 B-11 NMR 光谱以及红外光谱进行了表征。
Reaction of Na2[nido-7,8-Me2-7,8-C2B9H9] with [Ni2(mu-Br)2(eta3-C3H5)2] or [Pt2(mu-Br)2(eta-C3H5)2] in thf (tetrahydrofuran) gives the anionic species [M(eta3-C3H5)(eta 5-7,8-Me2-7,8-C2B9H9)]- (M = Ni or Pt) which have been isolated as their [NEt4]+ and [N(PPh3)2]+ salts 1a-1d. In the presence of suitable substrate molecules (L = CO or CNBu(t)), protonation (HBF4.Et2O) of the reagents 1 at low temperatures gives the neutral compounds [ML2-(eta5-7,8-Me2-7,8-C2B9H9)] (2a, M = Ni, L = CO; 2b, M = Ni, L = CNBu(t); 2c, M = Pt, L = CO; 2d, M = Pt, L = CNBu(t)). Dichloromethane solutions of the dicarbonylnickel complex 2a slowly decompose through loss of carbon monoxide to give a mixture of the isomeric dimetal species [Ni2(CO)2(eta5-7,8-Me2-7,8-C2B9H9)2] (3a), [Ni2(CO)2(eta5-7,8-Me2-7,8-C2B9H9)(eta5-2,7-Me2-2,7-C2B9H9)] (3b), and [Ni2(CO)2(eta5-2,7-Me2-2,7-C2B9H9)2] (3c). The molecular structure of 3c, in which the carborane CMe groups of both cages occupy vertices in different layers of the eta5-C2B9 nido-cages, was established by X-ray diffraction. Crystals are monoclinic, space group C2/c (No. 15), with a = 21.498(5) angstrom, b = 7.722(2) angstrom, c = 14.962(3) angstrom, beta = 98.21(2)degrees, and Z = 4. Each nickel atom is ligated by a terminal carbonyl group and by a 2,7-Me2-2,7-C2B9H9 carborane cage, the coordinated CBBBB ring of which displays pronounced nonplanarity. In addition, the metal-metal vector is spanned by two three-center, two-electron B-H half arrow pointing right Ni ''agostic'' interactions. Treatment of a CH2Cl2 solution of [N(PPh3)2][Pt(eta3-C3H5)(eta5-7,8-Me2-7,8-C2B9H9)] (1d) with HBF4.Et2O at ca. -78-degrees-C followed by addition of the alkyne PhC=CH affords the dimetal species [Pt2{mu-sigma,sigma':eta4-C(H)C(Ph)C(H)C(Ph)}(eta5-7,8-Me2-7,8-C2B9H9)2] (4), the structure of which has been established by X-ray diffraction. Crystals are triclinic, space group P1BAR (No. 2) with a = 13.317(2) angstrom, b = 16.783(4) angstrom, c = 17.289(4) angstrom, alpha = 64.94(2(degrees, beta = 83.31(2)degrees, gamma = 78.58(2)degrees, and Z = 4. Two alkyne molecules have coupled in a ''head-to-tail'' manner to give a bridging ''C4'' moiety that is sigma-bonded to one of the metal centers through the two terminal carbon atoms and eta4-bound to the second metal center. In addition, each platinum atom is ligated by a 7,8-Me2-7,8-C2B9H9 carborane cage bound in a pentahapto manner, with neither cage involved in exopolyhedral bonding. Protonation (HBF4.Et2O) of 1a in CH2Cl2 followed by addition of [Co2(CO)8] affords the trinuclear metal complex [Co2Ni(mu-CO)(CO)5(eta5-7,8-Me2-7,8-C2B9H9)] (5), in which the NiC2B9 metallacarborane cage forms two exopolyhedral B-H half arrow point right Co ''agostic'' interactions. In addition to the X-ray diffraction studies, the new compounds have been characterized by microanalysis, H-1, C-13, and B-11 NMR spectroscopy, and infrared spectroscopy.