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Trevor Janes Yael Diskin‐Posner David Milstein 《Angewandte Chemie (International ed. in English)》2020,59(12):4932-4936
A family of cationic boron complexes was synthesized, using a dianilidopyridine pincer ligand, which imposes in‐plane distortion of the geometry at boron towards T‐shaped. Reactivity of these cations toward hydride and base was investigated, and the utility of these cations as precursors to a variety of π‐conjugated BN heterocycles was demonstrated. 300 nm irradiation of a deprotonated pincer boron complex triggered a C?N cleavage/C?C formation yielding a dearomatized boryl imine, which has a structure akin to the long‐proposed intermediate in the photochemical Hofmann–Martius rearrangement. The photo‐rearrangement triggers relief of the distortion imposed by the pincer ligand. 相似文献
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Liqing Ma 《Journal of organometallic chemistry》2007,692(24):5331-5338
The reaction of 2,6-(2-{Me2NCH2}C6H4)2C6H3I (2) with Pd2(dba)3 produced the NCN diamine pincer complex [2,6-(2-Me2{NCH2}C6H4)2C6H3PdI] (3) by an oxidative addition route. The structural analysis of ligand precursor 2 revealed a syn-conformation in the solid state. Single crystal X-ray analysis of complex 3 revealed a conventional square planar geometry about the palladium center and a global C2 symmetric structure. Variable temperature and concentration NMR spectroscopic studies of complex 3 suggest an equilibrium between 3 and the dinuclear species [{2,6-(2-{Me2NCH2}C6H4)2C6H3Pd}2μ2-I]I in CDCl3 solution. An unusual carbonate complex [{2,6-(2-{Me2NCH2}C6H4)2C6H3Pd}3μ3-CO3]I3 (4) was also structurally characterized as a minor product during synthesis of 3. 相似文献
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Heba M. Refaat Atallh A. M. Alotaibi Necmi Dege Ayman El-Faham Saied M. Soliman 《Molecules (Basel, Switzerland)》2022,27(11)
2,4-bis (3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazine (BPMT) pincer ligand was used to synthesize the new [Zn(BPMT)(NCS)2] (1) and [Zn(BPMT)(Br)2] (2) complexes by a reaction with Zn(NO3)2·6H2O in the presence of either KSCN or KBr, respectively. The structure of complex 1 has been exclusively confirmed using single crystal X-ray diffraction. In this neutral heteroleptic complex, the BPMT is a pincer chelate coordinating the Zn(II) ion via three interactions with the two pyrazole moieties and the s-triazine core. Hence, BPMT is a tridentate NNN-chelate. The coordination environment of Zn(II) is completed by two strong interactions with two terminal SCN− ions via the N-atom. Hence, the Zn(II) is penta-coordinated with a distorted square pyramidal coordination geometry. Hirshfeld analysis indicated the predominance of H…H, H…C and N…H intermolecular interactions. Additionally, the S…H, S…C and S…N contacts are the most significant. The free ligand has no or weak antimicrobial, antioxidant and anticancer activities while the studied Zn(II) complexes showed interesting biological activity. Complex 1 has excellent antibacterial activity against B. subtilis (2.4 μg/mL) and P. vulgaris (4.8 μg/mL) compared to Gentamycin (4.8 μg/mL). Additionally, complex 1 (78.09 ± 4.23 µg/mL) has better antioxidant activity than 2 (365.60 ± 20.89 µg/mL). In addition, complex 1 (43.86 ± 3.12 µg/mL) and 2 (30.23 ± 1.26 µg/mL) have 8 and 12 times the anticancer activity of the free BPMT ligand (372.79 ± 13.64 µg/mL). 相似文献
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Frederik Rummel Frerk Wehmeyer Dr. Matthias Vogt Prof. Dr. Robert Langer 《欧洲无机化学杂志》2023,26(28):e202300313
The thioether-group-containing SNS-type pincer complex [({EtSCH2CH2}2NH)RuCl(H)(PPh3)] ( 2 ) exists in three different diastereomers ( 2 a – c ). The molecular structures obtained from single crystal X-Ray diffraction studies of all three isomers reveal a difference in the relative orientation of the respective EtS-groups, while other commonly observed diastereomers as the result of cis-/trans- or fac-/mer-isomerism are not observed. Chemical exchange between the three diastereomers 2 a – c was discovered by phase-sensitive 1H and 31P NOESY NMR spectroscopy, and further quantified by line shape analysis of 1H NMR spectra. The experimentally derived averaged Gibbs energies of activation for the interconversion of the isomers (65–70 kJ/mol) are in good agreement with the results obtained from DFT calculations, which suggest an inversion of the ligating sulfur atoms, although a dissociative pathway for the configurational inversion can be competitive. 相似文献