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2.
Mohammad Shakir Shahul Hameed Farha Firdaus Saji P. Varkey 《Transition Metal Chemistry》1995,20(2):142-143
Summary Adducts of dichlorosulphato bis(1,3-propylenediamine)-metal(II) complexes with dialkyltin dichlorides, [R2Sn(MeCN) 2]2[M(NH(CH2)3NH)2(SO3Cl)2] (M = Cr, Fe, Co, Ni or Cu; R = Me or n-Bu) have been prepared. The positive shift in the symmetric SO3 stretch and splitting of the doubly degenerate (E) modes in their i.r. spectra suggest a covalent linkage for the SO3Cl– group. The adducts are non-electrolytes; magnetic moments and ligand field data suggest that each SO3Cl– group is monodentate, generating an octahedral geometry around the metal ions, except for NiII where tetragonal distortion is observed.Author to whom all correspondence should be directed. 相似文献
3.
Summary The number and positions of the i.r. active modes in ethylenediamine complexes of M(SO3Cl)2 (M = Mn, Fe, Co, Ni or Cu) suggest that the SO3Cl– anion is covalently bound in these non-electrolytic complexes. Magnetic moments and ligand field data suggest that each SO3Cl– group is monodentate, giving an octahedral geometry around the metal ions. 相似文献
4.
A novel homotrifunctional conjugation reagent, 1,3,5-tris-(N-maleimidomethyl)benzene has been synthesized in high yield with minimum purification. The reactivity of this compound was examined by using l-cysteine as a nucleophile. 相似文献
5.
Aydin Tavman Naz M. Agh-Atabay Sadik Guner Fahrettin Gucin Basaran Dulger 《Transition Metal Chemistry》2007,32(2):172-179
2-(5-H/Me/Cl-1H-benzimidazol-2-yl)-phenol ligands form 1:1 electrolytes, 5-coordinate monometallic complexes with iron(III) nitrate. The geometry of the [Fe(L)(OH)(H2O)2](NO3) complexes was derived from theoretical calculation in DGauss/DFT level (DZVP basis set) on CACHE. In all of the complexes
the ligands are bidentate, via one imine nitrogen atom and phenolate oxygen atom. The coordination is completed with a hydroxide ion, and two water molecules,
adopting a distorted square pyramidal geometry. The structures of the compounds were confirmed on the basis of elemental analysis,
molar conductivity, magnetic moment, FT-Raman, FT-IR (mid-IR, far-IR), EPR and u.v.–vis. The antimicrobial activities of the
free ligands, their hydrochloride salts, and the complexes were evaluated using the disk diffusion method in dimethyl sulfoxide
(DMSO) as well as the minimal inhibitory concentration (MIC) dilution method, against nine bacteria and the results are compared
with several known antibiotic agents. Antifungal activities were reported for Candida albicans, Kluyveromyces fragilis, Rhodotorula rubra, Debaryomyces hansenii, Hanseniaspora guilliermondii, and the results were referenced against nystatin, ketaconazole, and clotrimazole antifungal agents. In most cases, the compounds
tested showed broad-spectrum (Gram+ & Gram− bacteria) activities that were either more active or as potent as the references. 相似文献
6.
Farah Naz Bibimaryam Mousavi Zhixiong Luo Christia Jabbour Philippe M. Heynderickx Somboon Chaemchuen Francis Verpoort 《应用有机金属化学》2019,33(5)
A series of spray dried zeolitic imidazolate frameworks (ZIFs = ZIF‐8, ZIF‐67, and Zn/Co‐ZIF) are used as a catalyst for the bulk ring‐opening polymerization of δ‐valerolactone without any co‐catalyst to generate polyvalerolactone. Interestingly, using the same catalyst under the same reaction conditions could manipulate the structure of the product polymer, and thus its physical properties. Thus, using a dried substrate leads to the formation of the cyclic polymer while a linear polymer was formed on using the commercially available substrate. An activated monomer mechanism has been suggested where the propagating zinc alkoxide undergoes an intramolecular transesterification to release cyclic or linear polyvalerolactone. The ROP of δ‐VL without drying shows that the polymeric zwitterions have little tendency to cyclize in the presence of moisture. At 140 °C, ZIF‐8 shows a superior catalytic activity resulting in the production of cyclic polyvalerolactone having a high molecular weight as compared to ZIF‐67 or Zn/Co‐ZIF due to the presence of highly active sites. The catalyst could be recycled and reused without any significant loss of catalytic activity. 相似文献
7.
Dennis Cao Dr. Michal Juríček Zachary J. Brown Dr. Andrew C.‐H. Sue Dr. Zhichang Liu Juying Lei Anthea K. Blackburn Dr. Sergio Grunder Dr. Amy A. Sarjeant Prof. Ali Coskun Prof. Cheng Wang Prof. Omar K. Farha Prof. Joseph T. Hupp Prof. J. Fraser Stoddart 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(26):8457-8465
We report the synthesis of two [2]catenane‐containing struts that are composed of a tetracationic cyclophane (TC4+) encircling a 1,5‐dioxynaphthalene (DNP)‐based crown ether, which bears two terphenylene arms. The TC4+ rings comprise either 1) two bipyridinium (BIPY2+) units or 2) a BIPY2+ and a diazapyrenium (DAP2+) unit. These degenerate and nondegenerate catenanes were reacted in the presence of Cu(NO3)2?2.5 H2O to yield Cu‐paddlewheel‐based MOF‐1050 and MOF‐1051. The solid‐state structures of these MOFs reveal that the metal clusters serve to join the heptaphenylene struts into grid‐like 2D networks. These 2D sheets are then held together by infinite donor–acceptor stacks involving the [2]catenanes to produce interpenetrated 3D architectures. As a consequence of the planar chirality associated with both the DNP and hydroquinone (HQ) units present in the crown ether, each catenane can exist as four stereoisomers. In the case of the nondegenerate (bistable) catenane, the situation is further complicated by the presence of translational isomers. Upon crystallization, however, only two of the four possible stereoisomers—namely, the enantiomeric RR and SS forms—are observed in the crystals. An additional element of co‐conformational selectivity is present in MOF‐1051 as a consequence of the substitution of one of the BIPY2+ units by a DAP2+ unit: only the translational isomer in which the DAP2+ unit is encircled by the crown ether is observed. The overall topologies of MOF‐1050 and MOF‐1051, and the selective formation of stereoisomers and translational isomers during the kinetically driven crystallization, provide evidence that weak noncovalent bonding interactions play a significant role in the assembly of these extended (super)structures. 相似文献
8.
Fatima Gul Naz Paliwal Sarvesh K. Saraf Shailendra K. 《Russian Journal of General Chemistry》2021,91(2):285-293
Russian Journal of General Chemistry - A number of novel 7-chloro-4-aminoquinoline derivatives have been efficiently synthesized by nucleophilic aromatic substitution reaction of... 相似文献
9.
Water‐Stable Zirconium‐Based Metal–Organic Framework Material with High‐Surface Area and Gas‐Storage Capacities 下载免费PDF全文
Dr. Oleksii V. Gutov Dr. Wojciech Bury Dr. Diego A. Gomez‐Gualdron Dr. Vaiva Krungleviciute Dr. David Fairen‐Jimenez Dr. Joseph E. Mondloch Dr. Amy A. Sarjeant Salih S. Al‐Juaid Prof. Dr. Randall Q. Snurr Prof. Dr. Joseph T. Hupp Prof. Dr. Taner Yildirim Prof. Dr. Omar K. Farha 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(39):12389-12393
We designed, synthesized, and characterized a new Zr‐based metal–organic framework material, NU‐1100 , with a pore volume of 1.53 ccg?1 and Brunauer–Emmett–Teller (BET) surface area of 4020 m2g?1; to our knowledge, currently the highest published for Zr‐based MOFs. CH4/CO2/H2 adsorption isotherms were obtained over a broad range of pressures and temperatures and are in excellent agreement with the computational predictions. The total hydrogen adsorption at 65 bar and 77 K is 0.092 g g?1, which corresponds to 43 g L?1. The volumetric and gravimetric methane‐storage capacities at 65 bar and 298 K are approximately 180 vSTP/v and 0.27 g g?1, respectively. 相似文献
10.
Detoxification of Chemical Warfare Agents Using a Zr6‐Based Metal–Organic Framework/Polymer Mixture 下载免费PDF全文
Dr. Su‐Young Moon Emmanuel Proussaloglou Gregory W. Peterson Dr. Jared B. DeCoste Morgan G. Hall Dr. Ashlee J. Howarth Prof. Joseph T. Hupp Prof. Omar K. Farha 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(42):14864-14868
Owing to their high surface area, periodic distribution of metal sites, and water stability, zirconium‐based metal–organic frameworks (Zr6‐MOFs) have shown promising activity for the hydrolysis of nerve agents GD and VX, as well as the simulant, dimethyl 4‐nitrophenylphosphate (DMNP), in buffered solutions. A hurdle to using MOFs for this application is the current need for a buffer solution. Here the destruction of the simulant DMNP, as well as the chemical warfare agents (GD and VX) through hydrolysis using a MOF catalyst mixed with a non‐volatile, water‐insoluble, heterogeneous buffer is reported. The hydrolysis of the simulant and nerve agents in the presence of the heterogeneous buffer was fast and effective. 相似文献