[((LZn)-L-Me-Zn-Dipp)(2)(mu-eta(2):eta(2)-PhN6Ph)] (3), which was synthesized by reaction of (L2Zn2)-L-Me-Zn-Dipp with PhN3, reacts with two equivalents of Me2Zn to give [(MeZn)(2)(mu-eta(2):eta(2)-PhN6Ph)] (2). The reaction of 2 with pyridine gave [(MeZn)(2)(mu-eta(2):eta(2)-PhN6Ph)(Py)(2)] (4), while reactions with H-acidic ligands ((LH)-L-Me-H-Mes, (LH)-L-Me-H-Ph) occurred with elimination of methane and formation of [((RLZn)-L-Me-Zn-Mes)(2)(mu-eta(2):eta(2)-PhN6Ph)] (1) and [((LZn)-L-Me-Zn-Ph)(2)(mu-eta(2):eta(2)-PhN6Ph)] (5). The reaction of 1 with two equivalents of MeLi yielded the heterobimetallic hexazene complex [(MeZn)(mu-eta(2):eta(2)-PhN6Ph)(Li)], which was found to undergo stepwise reaction with Me2AlCl to give [MeZn((mu-eta(2):eta(2)-PhN6Ph)AlMe2] and finally [(Me2Al)(2)(mu-eta(2):eta(2)-PhN6Ph)(thf)(2)] (6). Compounds 3-6 were characterized by elemental analysis, NMR spectroscopy, and single-crystal X-ray diffraction. Quantum chemical calculations were performed in order to investigate the electronic structure of 4' and 6' in more detail and to identify the absorption bands of the hexazene unit.
On the Chemistry of Zn−Zn Bonds, RZn−ZnR (R = [{(2,6-Pri2C6H3)N(Me)C}2CH]): Synthesis, Structure, and Computations
摘要:
Potassium reduction of RZn(mu-I)2Li(OEt2)2 (R = [{(2,6-Pri2C6H3)N(Me)C}2CH]) affords the second compound with a Zn-Zn bond, RZn-ZnR. The air- and moisture-sensitive title compound was characterized by 1H NMR, elemental analyses, and single-crystal X-ray diffraction. The Zn-Zn bond was determined to be 2.3586(7) A; this value is only about 0.05 A longer than the Zn-Zn bond reported for Cp*Zn-ZnCp* (Cp* = C5Me5), the first reported compound with a Zn-Zn bond. In addition, density functional theory (DFT) computations on related model RZn-ZnR compounds provide insight into the intriguing Zn-Zn bond.
作者:Hung Banh、Christian Gemel、Rüdiger W. Seidel、Roland A. Fischer
DOI:10.1039/c4cc08850f
日期:——
[Zn2]2+ as an analogue of the calomel dication [Hg2]2+ was isolated in the form of the solvent stabilized salt [Zn2(THF)6]2+[BAr4F]2−, for which the coordination environment is readily tuneable due to the lability of the solvent molecules.