Comparative analysis of self-aggregation of liquid crystalline Pt(II) complexes in solution and in neat films
作者:Alfiya F. Suleymanova、Yulia A. Yakovleva、Oleg S. Eltsov、Anastasiya O. Lantushenko、Maxim P. Evstigneev、Bertrand Donnio、Benoît Heinrich、Valery N. Kozhevnikov
DOI:10.1016/j.jorganchem.2021.121750
日期:2021.4
be essential for the emergence of liquidcrystalline behaviour. This pair of two similar compounds, non-mesomorphic complex and mesomorphic complex, was prepared as a model to assess the possible link of the self-aggregation in solution with the appearance of the liquidcrystallinity in molten state. NMR dilution studies in CDCl3 solution and X-ray diffusion study in neat films show qualitative similarity
Cyclometalation of 6-Phenyl-2,2′-Bipyridine and Iridium: Synthesis, Characterization, and Reactivity Studies
作者:Kenneth J. H. Young、Muhammed Yousufuddin、Daniel H. Ess、Roy A. Periana
DOI:10.1021/om900014h
日期:2009.6.22
Heating the potential tridentate 6-(4-R-phenyl)-2,2'-bipyridine ligand la (R = H), and derivatives 1b (R = CMe3) and 1c (R = OH), with IrCl3 hydrate in 2-methoxyethanol or acetone/H2O gave the unexpected bidentate cyclometalated NC dinuclear complexes [Ir(NC)Cl-2(C5H5N)](2) (2a-cPy), as the major product. Altering the ligand/metal ratio from 1:1 to 2:1 produced a mixture of bis-cyclometalated complexes, Ir(NNC)(NC)Cl (3a,b), with tridentate and bidentate binding modes. Using discrete Ir-I synthons, such as Ir(dmso)(3)Cl or [Ir(cyclooctene)(2)Cl](2), gave a complicated mixture of products. However, when [Ir(C2H4)(2)Cl](2) was used, then the desired tridentate cyclometalated Ir(NNC) complex Ir(NNC)Et(CH4)Cl (4) was synthesized cleanly. The dinuclear complex 2a-Py was converted to the corresponding mononuclear dichloride complexes Ir(NC)(NN)Cl-2 (5a) upon refluxing with 4,4'-di-tert-butylbipyridine in N,N-dimethylacetamide (DMA). Treatment of 5a with ZnMe2 gives Ir(NC)(NNtBu)MeCl (6a). Abstraction of the chloride with AgOTF yields Ir(NC)(NNtBu)MeOTf (7a). Complex 7a undergoes stoichiometric CH activation with arenes and shows catalytic activity for the H/D exchange between benzene and ( trifluoro)acetic acids.