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991.
The reaction of 3,8,13,18-tetramethyl-21H,23H-porphine-2,7,12,17-tetrapropionic acid or coproporphyrin-I (CPI) with the elements of 11 group have been studied. CPI is an anionic porphyrin that slowly reacts with copper ion to form CuIICPI and with silver ions to form AgIICPI, AgIIICPI complexes and colloidal silver. Gold ions do not form complexes with CPI, but, in the main, colloidal gold and some CPI-N-oxide. The kinetics of the reactions with copper and silver were spectrophotometerically studied and the rate constants were calculated. The identification and characterization of this water-soluble anionic porphyrin and its metal complexes have been performed by electrospray mass spectrometry (ESI-MS) that proved to be an excellent method for these determinations. The multiple charged parent ions for metal free ligand and their metal complexes were identified. 相似文献
992.
The X-ray crystal structure of 2-hydroxy-2-(1,4-bisoxo-6-hexanol)-1,1-biphenyl, 3, is presented. This molecule crystallizes in the monoclinic space group P21/n (a = 9.440(2), b = 12.679(3), c = 11.679(3) Å = 94.60(2)° V = 1382.5(5) Å3; Z = 4). One of the unique features of the X-ray structure of 3 is the intramolecular hydrogen bonding. The hydrogens of the phenolic and hydroxy groups occupies bridging positions via hydrogen bonding to an ether oxygen (O1) and a phenolic oxygen (O4), respectively. This hydrogen bonding does not affect the interplanar angle between phenyl rings (49.34°), which is in the range expected for ortho-disubstituted biphenyl compounds. The hydrogen bonding of this type explains why it is difficult to alkylate both phenoxy groups of 2,2-biphenol with tetrahydropyranyl protected 2-(2-chloroethoxy)ethanol. 相似文献
993.
Mirjana Antonijević Nikolić Jelena Antić Stanković Slađana B. Tanasković 《Journal of Coordination Chemistry》2018,71(10):1542-1559
New cationic tetranuclear Co(II) and neutral binuclear Cu(II) complexes with tpmc (N,N′,N″,N″′-tetrakis-(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane) and bridging pyromellitate ligand pma (tetraanion 1,2,4,5-benzenetetracarboxylic acid) were isolated. The composition of the compounds is proposed based on elemental analyses (C, H, N, M=Cu, Co), molar conductivity determination, UV-Vis, FTIR, EPR, LC-MS and reflectance spectroscopy, magnetic measurements, cyclic voltammetry, as well as TG and DTA. It is proposed that in [Co4(pma)(tpmc)2](ClO4)4·6H2O (1), cobalt(II) is six-coordinate out of cyclam rings and one OCO? from pma participates in coordination with one Co(II). In the case of [Cu2(pma)tpmc]?8H2O (2), one OCO? from pma bridges two Cu(II). The cytotoxic activity of 1 and 2 was tested against tumor cell lines human cervix adenocarcinoma (HeLa), estrogen-receptor-positive human breast cancer (MCF-7), human myelogenous leukemia (K562), and the human Caucasian Burkitt’s lymphoma (Ramos). The IC50 values for 1 and 2 were within the range 44.66 ± 2.39 to 152.40 ± 2.28 μM, and from 140.88 ± 3.51 to 192.05 ± 2.09 μM, respectively. Both 1 and 2 were tested for antimicrobial activity. We determined that minimal inhibitory concentration for 1 against Staphylococcus aureus, Bacillus subtilis, and Klebsiella pneumoniae was 25 mM. Complex 2 did not express activity against tested microbial strains. 相似文献
994.
A new type of strategy for photo-induced supramolecular polymerization based on hostguest interaction has been explored. A kind of monomer containing dibenzo-24-crown-8 (DB24C8) macrocycle and dibenzylammonium (DBA) site was designed and synthesized. The coumarin, as a photocleavable protector, was introduced to the end of the monomer whose polymerization can be irradiated by UV light via the hostguest interactions between DB24C8 moieties and DBA units. 相似文献
995.
报道了两种超分子配合物[Na(DB18C6)(CH_3OH)]_2W_4Mo_2O_(19)·(DB18C6)·(CH_3OH)(Ⅰ)和[Na(DB24C8)]_2W_1Mo_5O_(19)(Ⅱ)的合成方式,用元素分析、电子能谱、IR和1HNMR等手段进行了表征,并用X射线测定了晶体结构。结构分析表明:配合物(Ⅰ)属单斜晶系,空间群为P21/c,晶胞参数:α=1.8699(5)nm,b=1.9543(5)nm,c=2.2808(6)nm,β=112.87°,Z=4.冠醚与多酸根之间通过Na+在DB18C6空腔中的镶嵌和O—Na—O键的桥联结合在一起。超分子配合物(Ⅱ)则为Na+与DB24C8作用形成配位阳离子,然后与多酸阴离子静电吸引相结合。不同空腔孔径的冠醚与钼钨杂多酸配位时呈现出分子识别与选择性。 相似文献
996.
用凝胶法合成了标题配合物,并进行了元素分析、红外光谱、质谱及差热-热重等物性表征;用四圆衍射仪测定了它的晶体结构。晶体属三斜晶系、空间群P1,晶胞参数α=9.097(2),ι=15.754(3),(?)=16.556(2),(?)=88.08(1)°,(?)=81.29(1)°,(?)=86.62(2)°Z=2。结构分析表明,该配合物中冠醚与铵离子形成配阳离子;铋(Ⅲ)由硫氰酸根和氯离子配位,并以配体桥联形成链状聚合的配合阴离子,配合阴、阳离子主要以静电吸引形成配合物。 相似文献
997.
Yurij Simonov Luigi Pietro Battaglia Anna Bonamartini Corradi Sandra Ianelli Giorgio Pelosi Edward Ganin Nicolaj Lukjanenko 《Journal of inclusion phenomena and macrocyclic chemistry》1990,9(3):181-194
The crystal structures of inclusion compounds of 4-aminobenzenesulfamidine (sulfaguanidine) (L) with two dicyclohexano-18-crown-6 (DCH-6) isomers A(cis-syn-cis) and B(cis-anti-cis) have been determined by X-ray methods. The complexes exhibit 1:2 host-guest ratios. In fact the complex of isomer A is formulated as [DCH-6A·[L]H2O]L (complexI), while that of isomerB is DCH-6
B
L2 (complex I1).In the crystals, host and guests are connected by O-H...0 and N-H...O bonds. 相似文献
998.
Roy Buschbeck 《Journal of organometallic chemistry》2005,690(3):696-703
The synthesis of the allyloxymethyl-functionalized crown ethers of type CH2CHCH2OCH2[15-crown-5] (3a) and CH2CHCH2OCH2[18-crown-6] (3b) can be achieved by treatment of HOCH2[15-crown-5] (1a) and HOCH2[18-crown-6] (1b) with CH2CHCH2Br (2) in presence of KOH. The hydrosilylation of 3a and 3b with Si(CH2CH2CH2SiMe2H)4 (4) and Si(CH2CH2CH2SiMe(CH2CH2CH2SiMe2H)2)4 (6) in presence of the Karstedt catalyst affords the respective crown ether end-capped carbosilane dendrimers Si(CH2CH2CH2SiMe2CH2CH2CH2OCH2[15-crown-5])4 (5a), Si(CH2CH2CH2SiMe2CH2CH2CH2OCH2[18-crown-6])4 (5b), Si(CH2CH2CH2SiMe(CH2CH2CH2SiMe2CH2CH2CH2OCH2[15-crown-5])2)4 (7a) and Si(CH2CH2CH2SiMe(CH2CH2CH2SiMe2CH2CH2CH2OCH2[18-crown-6])2)4 (7b). The latter dendrimers are obtained in almost quantitative yield. The complexation behaviour of 5 and 7 towards different alkali metal cations is discussed. 相似文献
999.
1000.
KI-醚类催化剂催化二氧化碳和环氧乙烷合成碳酸乙烯酯反应研究 总被引:7,自引:0,他引:7
合成了5个含有金属铁的环醚Fe(CO)3L(L1=Ph2P(CH2CH2O)2CH2CH2PPh2,L2=Ph2P(CH2CH2O)4CH2CH2PPh2,L3=OPh[(OCH2CH2)PPh2]2,L4=OPh[OCH2CH2)2PPh2]2)和[Fe(CO3)]2L5(L5=[Ph2PCH2CH2OCH2CH2PPh2]2).对它们进行了元素分析,并用红外光谱和核磁共振谱进行了结构表征.用KI+醚类为催化剂,催化二氧化碳与环氧乙烷反应生成碳酸乙烯酯,反应选择性大于96.9%.催化机理为碱催化,催化剂的活性受醚的影响.能和K+形成稳定配合物的醚可提高催化剂的活性.含金属铁的环醚和普通醚类相似,可以和钾离子作用,提高阴离子的亲核催化性能. 相似文献