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1.
Interaction of [Ru(NO)Cl3(PPh3)2] with K[N(R2PS)2] in refluxing N,N-dimethylformamide afforded trans-[Ru(NO)Cl{N(R2PS)2}2] (R = Ph (1), Pri (2)). Reaction of [Ru(NO)Cl3(PPh3)2] with K[N(Ph2PSe)2] led to formation of a mixture of trans-[Ru(NO)Cl{N(Ph2PSe)2}2] (3) and trans-[Ru(NO)Cl{N(Ph2PSe)2}{Ph2P(Se)NPPh2}] (4). Reaction of Ru(NO)Cl3 · xH2O with K[N(Ph2PO)2] afforded cis-[Ru(NO)(Cl){N(Ph2PO)2}2] (5). Treatment of [Rh(NO)Cl2(PPh3)2] with K[N(R2PQ)2] gave Rh(NO){N(R2PQ)2}2] (R = Ph, Q = S (6) or Se (7); R = Pri, Q = S (8) or Se (9)). Protonation of 8 with HBF4 led to formation of trans-[Rh(NO)Cl{HN(Pri2PS)2}2][BF4]2 (10). X-ray diffraction studies revealed that the nitrosyl ligands in 2 and 4 are linear, whereas that in 9 is bent with the Rh–N–O bond angle of 125.7(3)°.  相似文献   

2.
The synthesis, characterization and thermal behavior of new monomeric allylpalladium (II) complexes with dichalcogenoamidodiphosphinate anions are reported. The complexes [R = H, R′ = Pri, E = S (1a); R = H, R′ = Pri, E = Se (1b); R = H, R′ = Ph, E = S (1c); R = H, R′ = Ph, E = Se (1d); R = Me, R′ = Pri, E = S (2a); R = Me, R′ = Pri, E = Se (2b); R = Me, R′ = Ph, E = S (2c); R = Me, R′ = Ph, E = Se (2d)] have been prepared by room temperature reaction of [Pd(η3-CH2C(R)CH2)(acac)] (acac = acetylacetonate) with dichalcogenoimidodiphosphinic acids in acetonitrile solution. The complexes have been characterized by multinuclear NMR (1H, 13C{1H}, 31P{1H}, 77Se{1H}), FT-IR and elemental analyses. The crystal structures of complexes 1a, 1d and 2d have been reported and they consist of a six-membered PdE2P2N ring (E = S for 1a and Se for 1d and 2d) and an allyl group, C3H4R(R = H for 1a and 1d and Me for 2d). Thermogravimetric studies have been carried out for few representative complexes. The complexes thermally decompose in argon atmosphere to leave a residue of palladium chalcogenides, which have been characterized by PXRD, SEM and EDS.  相似文献   

3.
4.
5.
This work presents a systematic theoretical study on Cu(I) and Cu(II) cations in variable hydrogen sulfide-aqua-ammine ligand fields. These ligands model the biologically most common environment for Cu ions. Molecular structures of the complexes were optimized at the density functional theory (DFT) level. Subsequent thorough energy analyses revealed the following trends: (i) The ammine complexes are the most stable, followed by those containing the aqua and hydrogen sulfide ligands, which are characterized by similar stabilization energies. (ii) The most preferred Cu(I) coordination number is 2 in ammine or aqua ligand fields. A qualitatively different binding picture was obtained for complexes with H(2)S ligands where the 4-coordination is favored. (iii) The 4- and 5-coordinated structures belong to the most stable complexes for Cu(II), regardless of the ligand types. Vertical and adiabatic ionization potentials of Cu(I) complexes were calculated. Charge distribution (using the natural population analysis (NPA) method) and molecular orbital analyses were performed to elucidate the nature of bonding in the examined systems. The results provide in-depth insight into the Cu-binding properties and can be, among others, used for the calibration of bioinorganic force fields.  相似文献   

6.
Water-soluble cationic corrole derivatives were designed and synthesized, and the first observation of their interactions with the telomeric G-quadruplex was made.  相似文献   

7.
8.
The synthesis of a range of alkyl/chloro-gallium alkoxide and amido/alkoxide compounds was achieved via a series of protonolysis and alcoholysis steps. The initial reaction involved the synthesis of [Me(Cl)Ga{N(SiMe(3))(2)}](2) (1) via methyl group transfer from the reaction of GaCl(3) with two equivalents of LiN(SiMe(3))(2). Reaction of 1 with varying amounts of ROH resulted in the formation of [Me(Cl)Ga(OR)](2) (2, R = CH(2)CH(2)OMe; 3, CH(CH(3))CH(2)NMe(2)), [Me(Cl)Ga{N(SiMe(3))(2)}(μ(2)-OR)Ga(Cl)Me] (4, R = CH(2)CH(2)NMe(2)), or [MeGa(OR)(2)] (5, R = CH(CH(3))CH(2)NMe(2)). Compound 4 represents an intermediate in the formation of dimeric complexes, of the type [Me(Cl)Ga(OR)](2), when formed from compound [Me(Cl)Ga{N(SiMe(3))(2)}](2). A methylgallium amido/alkoxide complex [MeGa{N(SiMe(3))(2)}(OCH(2)CH(2)OMe)](2) (6) was isolated when 2 was further reacted with LiN(SiMe(3))(2). In addition, reaction of 2 with HO(t)Bu resulted in a simple alcohol/alkoxide exchange and formation of [Me(Cl)Ga(O(t)Bu)](2) (7). In contrast to the formation of 1, the in situ reaction of GaCl(3) with one equivalent of LiN(SiMe(3))(2) yielded [Cl(2)Ga{N(SiMe(3))(2)}](2) in low yield, where no methyl group transfer has occurred. Reaction of alcohol with [Cl(2)Ga{N(SiMe(3))(2)}](2) was then found to yield [Cl(2)Ga(OR)](2) (8, R = CH(2)CH(2)NMe(2)), and further reaction of 8 with LiN(SiMe(3))(2) yielded the gallium amido alkoxide complex, [ClGa{N(SiMe(3))(2)}(OR)](2) (9, R = CH(2)CH(2)NMe(2)), similar to 6. The structures of compounds 4, 5, 7, and 8 have been determined by single-crystal X-ray diffraction.  相似文献   

9.
Solvent extraction of trivalent group 13 metal cations such as aluminum, gallium and indium with tripod quadridentate phenolic ligand, tris(2-hydroxy-3,5-dimethylbenzyl)amine (H(3)tdmba), was investigated as fundamental study for their mutual separation. Gallium was extracted almost quantitatively as Ga(tdmba) (logK(ex)=-6.66+/-0.06 on using chloroform as extraction solvent), whereas aluminum and indium were hardly extracted due to steric hindrance on complexation of them with the ligand. The extracted Ga species was estimated as trigonal bipyramidal complex with one H(2)O molecule. Furthermore, extractability of Ga was increased by changing the ligand to more acidic tris(5-chloro-2-hydroxy-3-methylbenzyl)amine (H(3)tcmba) (logK(ex)=-6.18+/-0.18 on using dichloroethane as extraction solvent).  相似文献   

10.
Qiao J  Wang LD  Duan L  Li Y  Zhang DQ  Qiu Y 《Inorganic chemistry》2004,43(16):5096-5102
By introducing tridentate Schiff base ligands, a binuclear gallium complex with mixed ligands, bis(salicylidene-o-aminophenolato)-bis(8-quinolinolato)-bis-gallium(III) [Ga(2)(saph)(2)q(2)], has been synthesized and structurally characterized by single-crystal X-ray crystallography. Crystal data for C(44)H(30)Ga(2)N(4)O(6) are as follows: space group, triclinic, P; a = 11.357(3) A, b = 12.945(3) A, c = 12.947(3) A, alpha = 103.461(15) degrees, beta = 100.070(7) degrees, gamma = 96.107(18) degrees, Z = 2. This complex was identified as a dimeric complex of hexacoordinated gallium with strong intermolecular and intramolecular pi-pi stacking interactions between the pyridyl/pyridyl rings. The thermal analysis showed that Ga(2)(saph)(2)q(2) can readily form a stable amorphous glass with a high glass transition temperature (T(g) = 204 degrees C), which is 27 degrees C higher than that of tris(8-hydroxyquinolinolate)aluminum (Alq(3)). In addition, a high photoluminescence efficiency (phi(PL)) of 0.318 in DMF has been demonstrated, although the central gallium atom can result in heavy-atom quenching. Organic light-emitting diodes (OLEDs) based on this complex displayed a turn-on voltage as low as 2.5 V and a high efficiency. Even at a low doping concentration of 1%, the doped Ga(2)(saph)(2)q(2) devices with 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) as the dopant exhibited excellent red emission centered at 628 nm with improved durability, compared with the case of Alq(3) as the host. These distinguishing properties of Ga(2)(saph)(2)q(2) make it a good candidate as a novel electron-transporting and emitting material for OLEDs.  相似文献   

11.
Many of the essential metalloproteins are located in the cell, whose cytoplasmic fluid contains several small inorganic anions, such as Cl-, NO2-, NO3-, H2PO4-, and SO4(2-), that play an indispensable role in determining the cell's volume, regulating the cell's pH, signal transduction, muscle contraction, as well as cell growth and metabolism. However, the physical principles governing the competition between these abundant, intracellular anions and protein or nucleic acid residues in binding to cytoplasmic metal cations such as Na+, K+, Mg2+, and Ca2+ are not well understood; hence, we have delineated the physicochemical basis for this competition using density functional theory in conjunction with the continuum dielectric method. The results show that the metal cation can bind to its target protein against a high background concentration of inorganic anions because (i) desolvating a negatively charged Asp/Glu carboxylate in a protein cavity costs much less than desolvating an inorganic anion in aqueous solution and (ii) the metal-binding site acts as a polydentate ligand that uses all its ligating entities to bind the metal cation either directly or indirectly. The results also show that the absolute hydration free energy of the "alien" anion as well as the net charge and relative solvent exposure of the metal-binding protein cavity are the key factors governing the competition between protein and inorganic ligands for a given cytoplasmic metal cation. Increasing the net negative charge of the protein cavity, while decreasing the number of available amide groups for metal binding, protects the metal-bound ligands from being dislodged by cellular anions, thus revealing a "protective" role for carboxylate groups in a protein cavity, in addition to their role in high affinity metal-binding.  相似文献   

12.
A series of transition-metal complexes of N,N',N',N'-tetra(3-hydroxypropyl)cyclam (L1) are reported. The X-ray structures of the compounds reveal pendant arm coordination of one of the alcohol groups to give square-pyramidal metal centres with simultaneous hydrogen bonding to the counter anions. Ligand L1 has been elaborated to form a series of macrotricyclic derivatives that form 1 ratio 1 complexes with Cu(II) and Ni(II). The X-ray structure of the tetrahydrate and protonated forms of L1 are also reported.  相似文献   

13.
A series of cationic, neutral, and anionic allylgallium complexes has been isolated and fully characterized. It includes neutral [Ga(η(1)-C(3)H(5))(3)(L)] (1, L = THF; 2, L = OPPh(3)), cationic [Ga(η(1)-C(3)H(5))(2)(THF)(2)](+)[A](-) (3, [A](-) = [B(C(6)F(5))(4)](-); 4, [A](-) = [B(C(6)H(3)Cl(2))(4)](-)), as well as anionic [Cat](+)[Ga(η(1)-C(3)H(5))(4)](-) (5, [Cat](+) = K(+); 6, [Cat](+) = [K(dibenzo-18-c-6](+); 7, [Cat](+) = [PPh(4)](+)). Binding modes of the allyl ligand in solution and in the solid state have been studied comparatively. Single crystal X-ray analyses revealed a four-coordinate neutral gallium center in 2, a five-coordinate cationic gallium center in 4 and [4·THF], and a four-coordinate anionic gallium center with a bridging μ(2)-η(1):η(2) coordination mode of the allyl ligand in 6. The reactivity of this series of allylgallium complexes toward benzophenone and N-heteroaromatics has been investigated. Counterion effects have also been studied. Reactions of 1 and 5 with isoquinoline revealed the first examples of organogallium complexes reacting under 1,2-insertion with pyridine derivatives.  相似文献   

14.
15.
Russian Chemical Bulletin - A series of new paramagnetic six-coordinate gallium complexes based on 3,6-di-tert-butyl-o-benzoquinone with N-donor ligands, such as pyridine (Py), 2,2′-dipyridyl...  相似文献   

16.
17.
9-Bromo-7,12-dihydroindolo[3,2-d][1]benzazepin-6-ylhydrazine was reacted with 2-acetylpyridine to give a Schiff base as a potential tridentate ligand. The reaction of this ligand with gallium chloride afforded complexes of 1:1 and 2:1 stoichiometry. The results of X-ray diffraction studies of the ligand and both gallium complexes are reported and compared with the data for a related gallium complex with a Schiff base obtained from 9-bromo-7,12-dihydroindolo[3,2-d][1]benzazepin-6-ylhydrazine and 2-hydroxybenzaldehyde.   相似文献   

18.
Synthesis of the cyclic aluminatophosphazene ring N(PCl2NMe)2AlMeCl (5) has been achieved via a skeletal transmetalation reaction between AlMe3 and the boratophosphazene N(PCl2NMe)2BCl2 (1). Reaction of 5 with various halogenated Lewis acids such as GaCl3 yielded the fully chlorinated aluminum heterocycle N(PCl2NMe)2AlCl2 (8) through a methyl-halogen exchange process. In contrast, treatment of 5 with excess AlMe3 resulted in complete methylation at aluminum to give N(PCl2NMe)2AlMe2 (6). Compound 5 was reacted with various Ag+ salts with weakly coordinating anions, including Ag[OSO2CF3], which afforded the triflate-substituted heterocycle N(PCl2NMe)2AlMe(OSO2CF3) (9). The reaction of 5 with Ag[BF4] surprisingly produced the previously known fluorinated boratophosphazene N(PCl2NMe)2BF2 (10). The transformation of 1 to 5 and then to 10 represents a rare, formally reversible, skeletal transmetalation process involving boron and aluminum. Treatment of 5 with Ag[PF6] led to the insertion of phosphorus in place of aluminum to form the novel zwitterionic fluorinated phosphorus(V) heterocycle N(PCl2NMe)2PF4 (11). The ethyl-substituted aluminatophosphazene N(PCl2NMe)2AlMeEt (14) reacted cleanly with a 1:1 mixture of [Ph3C][B(C6F5)4] and THF to give the novel donor-stabilized alumazine-phosphazene hybrid cation, [7.THF]+, as the [B(C6F5)4]- salt [N(PCl2NMe)2AlMe.THF][B(C6F5)4] (15).  相似文献   

19.
《Tetrahedron letters》1987,28(16):1749-1752
Series of peptide-based lariat ethers derived from aza-18-crown-6 and bibracchial lariat ethers (BiBLEs) based on 4,13-diaza-18-crown-6 have been prepared. Sidearms incorporate inter alia the amino acids glycine, alanine, phenylalanine, leucine, isoleucine, and valine. Cation binding affinities for Na+ and K+ are reported.  相似文献   

20.
Binding of alkali metal cations (AMCs) by 1,3-alternate, ionised calix[4]arene-benzocrown-6 ligands was investigated by isothermal calorimetric titration in methanol. The groups of –C(O)NHSO2CH3 and more acidic –C(O)NHSO2CF3 were attached to the 1,3-alternate calix[4]arene-benzocrown-6 skeleton in two locations. In one series, the acidic group was attached to the para position of one aromatic ring in the calixarene framework, thereby positioning it over the polyether cavity. In the other series, the ionisable group was a substituent on the benzo group in the polyether ring. This oriented the acidic group away from the crown ether cavity. For these calixcrown ligands, the effects of the location of the ionisable group and its acidity and the identity of the AMC on the binding constant, enthalpy and entropy of complexation are assessed.  相似文献   

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