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Junwei Zhao - One of the best experts on this subject based on the ideXlab platform.
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first Dimethyltin functionalized rare earth incorporated tellurotungstates consisting of b α tew7o28 and w5o18 mixed building units
Inorganic Chemistry, 2018Co-Authors: Jinglin Liu, Mengtian Jin, Lijuan Chen, Junwei ZhaoAbstract:The facile one-step assembly reaction of Na2WO4·2H2O, Sn(CH3)2Cl2, RE(NO3)3·6H2O and K2TeO3 in the presence of dimethylamine hydrochloride as an organic solubilizing agent in acidic aqueous solution resulted in a family of Dimethyltin-functionalized rare-earth (RE) incorporated tellurotungstates consisting of {B-α-TeW7O28} and {W5O18} mixed building units [H2N(CH3)2]8Na4H2[RE2(OH)(B-α-TeW7O28)Sn2(CH3)4(W5O18)]2·18H2O [RE = ErIII (1), YbIII (2), HoIII (3), YIII (4)]. The most striking structural characteristic of 1–4 is that they all contain a novel tetrameric S-shaped [RE2(OH)(B-α-TeW7O28)Sn2(CH3)4(W5O18)]214– moiety simultaneously including two pentavacant Keggin [B-α-TeW7O28]12– and two monovacant Lindqvist [W5O18]6– fragments connected by RE and Dimethyltin linkers. To the best of our knowledge, such Dimethyltin-functionalized RE-containing tellurotungstates have not been reported before. The visible or NIR solid-state emission spectra of 1 and 3 display the characteristic emission bands arising from E...
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First Dimethyltin-Functionalized Rare-Earth Incorporated Tellurotungstates Consisting of {B-α-TeW7O28} and {W5O18} Mixed Building Units
2018Co-Authors: Jinglin Liu, Mengtian Jin, Lijuan Chen, Junwei ZhaoAbstract:The facile one-step assembly reaction of Na2WO4·2H2O, Sn(CH3)2Cl2, RE(NO3)3·6H2O and K2TeO3 in the presence of dimethylamine hydrochloride as an organic solubilizing agent in acidic aqueous solution resulted in a family of Dimethyltin-functionalized rare-earth (RE) incorporated tellurotungstates consisting of {B-α-TeW7O28} and {W5O18} mixed building units [H2N(CH3)2]8Na4H2[RE2(OH)(B-α-TeW7O28)Sn2(CH3)4(W5O18)]2·18H2O [RE = ErIII (1), YbIII (2), HoIII (3), YIII (4)]. The most striking structural characteristic of 1–4 is that they all contain a novel tetrameric S-shaped [RE2(OH)(B-α-TeW7O28)Sn2(CH3)4(W5O18)]214– moiety simultaneously including two pentavacant Keggin [B-α-TeW7O28]12– and two monovacant Lindqvist [W5O18]6– fragments connected by RE and Dimethyltin linkers. To the best of our knowledge, such Dimethyltin-functionalized RE-containing tellurotungstates have not been reported before. The visible or NIR solid-state emission spectra of 1 and 3 display the characteristic emission bands arising from ErIII and HoIII centers. Moreover, various 1-Er/Yb co-doped samples were prepared by controlling different mass ratio of Er(NO3)3·6H2O/Yb(NO3)·6H2O in the range of 0.96:0.04–0.02:0.98. In the visible region, the emission intensity of the 1-Er0.40/Yb0.60 co-doped sample reaches the maximum at the mass ratio of Er(NO3)3·6H2O/Yb(NO3)·6H2O being 0.40:0.60, and this observation is mainly derived from the fact that the Yb3+ ions can sensitize the Er3+ ions to enhance the emission intensity in the visible region. However, no such phenomenon for the 1-Er/Yb co-doped samples is seen in the NIR region. Besides, the upconversion spectra of the 1-Er/Yb co-doped samples were first observed. In addition, the thermal stabilities of 1–4 were also investigated on the crystalline samples and the thermal decomposition process of 1 has been deeply studied
Silvio Sammartano - One of the best experts on this subject based on the ideXlab platform.
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sequestration of alkyltin iv compounds in aqueous solution formation stability and empirical relationships for the binding of Dimethyltin iv cation by n and o donor ligands
Bioinorganic Chemistry and Applications, 2009Co-Authors: Agatino Casale, Concetta De Stefano, Giuseppe Manfredi, Demetrio Milea, Silvio SammartanoAbstract:The sequestering ability of polyamines and aminoacids of biological and environmental relevance (namely, ethylenediamine, putrescine, spermine, a polyallylamine, a branched polyethyleneimine, aspartate, glycinate, lysinate) toward Dimethyltin(IV) cation was evaluated. The stability of various Dimethyltin(IV) / ligand species was determined in NaClaq at t = 25°C and at different ionic strengths (0.1 ≤ I/mol L−1 ≤ 1.0), and the dependence of stability constants on this parameter was modeled by an Extended Debye-Huckel equation and by Specific ion Interaction Theory (SIT) approach. At I = 0.1 mol L−1, for the ML species we have log K = 10.8, 14.2, 12.0, 14.7, 11.9, 7.7, 13.7, and 8.0 for ethylenediamine, putrescine, polyallylamine, spermine, polyethyleneimine, glycinate, lysinate, and aspartate, respectively. The sequestering ability toward Dimethyltin(IV) cation was defined by calculating the parameter pL50 (the total ligand concentration, as −log CL, able to bind 50% of metal cation), able to give an objective representation of this ability. Equations were formulated to model the dependence of pL50 on different variables, such as ionic strength and pH, and other empirical predictive relationships were also found.
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Research Article Sequestration of Alkyltin(IV) Compounds in Aqueous Solution: Formation, Stability, and Empirical Relationships for the Binding
2009Co-Authors: O-donor Lig, Agatino Casale, Concetta De Stefano, Demetrio Milea, Silvio SammartanoAbstract:The sequestering ability of polyamines and aminoacids of biological and environmental relevance (namely, ethylenediamine, putrescine, spermine, a polyallylamine, a branched polyethyleneimine, aspartate, glycinate, lysinate) toward Dimethyltin(IV) cation was evaluated. The stability of various Dimethyltin(IV) / ligand species was determined in NaClaq at t = 25◦C and at different ionic strengths (0.1 ≤ I/mol L −1 ≤ 1.0), and the dependence of stability constants on this parameter was modeled by an Extended Debye-Hückel equation and by Specific ion Interaction Theory (SIT) approach. At I = 0.1molL −1, for the ML species we have log K = 10.8, 14.2, 12.0, 14.7, 11.9, 7.7, 13.7, and 8.0 for ethylenediamine, putrescine, polyallylamine, spermine, polyethyleneimine, glycinate, lysinate, and aspartate, respectively. The sequestering ability toward Dimethyltin(IV) cation was defined by calculating the parameter pL50 (the total ligand concentration, as−log CL, abletobind50%ofmetalcation),abletogiveanobjective representation of this ability. Equations were formulated to model the dependence of pL50 on different variables, such as ionic strength and pH, and other empirical predictive relationships were also found. Copyright © 2009 Agatino Casale et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1
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thermodynamic and spectroscopic study for the interaction of Dimethyltin iv with l cysteine in aqueous solution
Biophysical Chemistry, 2008Co-Authors: Paola Cardiano, Concetta De Stefano, Ottavia Giuffre, Silvio SammartanoAbstract:Thermodynamic and spectroscopic properties of the species formed by Dimethyltin(IV) cation with L-cysteine (cys) were studied by potentiometric, calorimetric, UV and NMR investigations in aqueous solution. The resulting speciation model showed the formation of five complex species: (CH(3))(2)Sn(cys)H(+), (CH(3))(2)Sn(cys)(0), (CH(3))(2)Sn(cys)OH(-), (CH(3))(2)Sn(cys)(2)H(-), (CH(3))(2)Sn(cys)(2)(2-). The stability and the formation percentages, for the mononuclear mixed species in particular, are very high, in a wide pH range. Thermodynamic parameters indicate that the enthalpy values are exothermic and the enthalpic contribution to the stability is higher than entropic one. Individual UV spectra of cys and Dimethyltin(IV)-cys species were calculated. Spectroscopic results of UV and (1)H NMR investigations fully confirm the speciation model. The structures calculated from NMR investigations show that all the species have an eq-(CH(3))(2)-tbp structure.
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speciation of phytate ion in aqueous solution Dimethyltin iv interactions in naclaq at different ionic strengths
Biophysical Chemistry, 2005Co-Authors: Concetta De Stefano, Demetrio Milea, Silvio SammartanoAbstract:Abstract As the introduction of a systematic study on the sequestering ability of phytate (Phy) towards heavy metal and organometal cations, this paper describes the results of an investigation (at t = 25 °C by potentiometry, ISE-H + glass electrode) of its interactions with Dimethyltin(IV) cation [(CH 3 ) 2 Sn 2+ , DMT] in NaCl aqueous solutions at different ionic strengths (0.1 ≤ I (mol L −1 ) ≤ 1), in the pH range 2.5 ≤ pH ≤ 8.5 and considering metal to ligand ratios 1:1 ≤ DMT:Phy ≤ 4:1. We observed the formation of 18 DMT i H j Phy (12−2 i − j )− species: with i = 1 and 0 ≤ j ≤ 7; i = 2 and 0 ≤ j ≤ 5; i = 3 and 0 ≤ j ≤ 3. Their complex formation constant values are fairly dependent on ionic strength and this dependence was modeled by a Debye-Huckel type equation. The speciation of phytic acid and Dimethyltin(IV) is also dependent on the metal to ligand ratio; the dependence of the stability of phytate-Dimethyltin(IV) species on both the phytate protonation step and the number of cations bound to the ligand has been modeled and an empirical predictive relationship is also proposed. From the results obtained it emerged that phytate has very good sequestering ability towards (CH 3 ) 2 Sn 2+ . Comparisons are made with other ligands, such as ethylenediamine- N , N , N ′, N ′-tetraacetic acid (EDTA) and phosphate.
Ram A Vishwakarma - One of the best experts on this subject based on the ideXlab platform.
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Dimethyltin dichloride catalyzed regioselective alkylation of cis 1 2 diols at room temperature
Journal of Organic Chemistry, 2015Co-Authors: Varma Saikam, Saidulu Dara, Mahipal Yadav, Parvinder Pal Singh, Ram A VishwakarmaAbstract:Here, we have developed a mild and general method for the regioselective installation of benzyl, allyl, para-methoxybenzyl and naphthyl groups on cis-1,2-diols. The optimized method operates at room temperature using Dimethyltin dichloride as catalyst and silver oxide as an additive. The present method works well with both sugars (such as mono- and disaccharides) and nonsugars (such as inositols, propan-1,2-diol, 1,2-cycloalkanediols and anhydroerythritol) and also provides comparatively better functional group compatibility.
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Dimethyltin Dichloride Catalyzed Regioselective Alkylation of cis-1,2-Diols at Room Temperature
2015Co-Authors: Varma Saikam, Saidulu Dara, Mahipal Yadav, Parvinder Pal Singh, Ram A VishwakarmaAbstract:Here, we have developed a mild and general method for the regioselective installation of benzyl, allyl, para-methoxybenzyl and naphthyl groups on cis-1,2-diols. The optimized method operates at room temperature using Dimethyltin dichloride as catalyst and silver oxide as an additive. The present method works well with both sugars (such as mono- and disaccharides) and nonsugars (such as inositols, propan-1,2-diol, 1,2-cycloalkanediols and anhydroerythritol) and also provides comparatively better functional group compatibility
Enbo Wang - One of the best experts on this subject based on the ideXlab platform.
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Dimethyltin functionalized cyclic selenotungstates based on se2w12 units
Dalton Transactions, 2018Co-Authors: Weichao Chen, Xinlong Wang, Chao Qin, Kuizhan Shao, Enbo WangAbstract:Two Dimethyltin-functionalized selenotungstates have been obtained: K4Na14[Sn(CH3)2Se6W24O94]·16H2O (1) and K8Na18[Sn(CH3)2Se6W40O145(H2O)2]Cl2·41H2O (2). They both remain cyclic selenotungstates based the on {Se2W12} units, where (CH3)2Sn2+ moieties were first introduced into "pure" POMs wheels.
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trimeric hexa Dimethyltin functionalized selenotungstate sn ch3 2 ch3coo 3 sn ch3 2 3 se2w18o62 oh h2o 3 18
CrystEngComm, 2016Co-Authors: Weichao Chen, Xinlong Wang, Chao Qin, Kuizhan Shao, Hongying Zang, Enbo WangAbstract:The trimeric organic–inorganic hybrid selenotungstate(IV) [{Sn(CH3)2(CH3COO)}3{Sn(CH3)2}3{Se2W18O62(OH)(H2O)}3]18− is composed of three Wells–Dawson-type {α-Se2W18} fragments and six {(CH3)2Sn2+} groups involving the first reported carboxyl-modified Dimethyltin moieties, exhibiting photocatalytic H2 evolution activity.
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assembly of tetrameric Dimethyltin functionalized selenotungstates from nanoclusters to one dimensional chains
Chemical Communications, 2015Co-Authors: Weichao Chen, Chao Qin, Kuizhan Shao, Enbo Wang, Hongying Zang, Hongsheng LiuAbstract:Two unprecedented tetrameric selenotungstates based on different Wells–Dawson-type fragments have been obtained: the {Sn7Se8W54} nanocluster exhibiting photocatalytic H2 evolution activity and the {Sn16Se11W56} chain, which are the first Dimethyltin-functionalized selenotungstates reported and contain the unique {β-Se2W15} and {γ-Se2W14} building blocks, respectively.
Rufen Zhang - One of the best experts on this subject based on the ideXlab platform.
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(1984). Experimental
2009Co-Authors: Yuerong Wang, Rufen Zhang, Crystal Data, Mo K Radiation, Bruker Smart Ccd Area-detectorAbstract:catena-Poly[[Dimethyltin(IV)]-l-cis-cyclohexane-1,2-dicarboxylato
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synthesis and crystal structure of a new macrocyclic Dimethyltin iv complex with 5 phenyl 1 3 4 oxadiazole 2 thiol linked by intermolecular cs o non bonded weak interactions
Inorganica Chimica Acta, 2007Co-Authors: Guangru Tian, Rufen ZhangAbstract:Abstract A new macrocycle Dimethyltin(IV) complex 1 has been synthesized by the reaction of 5-phenyl-1,3,4-oxadiazole-2-thiol with Dimethyltin dichloride in the presence of sodium ethoxide. The complex 1 has been characterized by elemental, IR, 1 H, 13 C, 119 Sn NMR spectra and X-ray crystallography diffraction analyses. X-ray data reveal that a 24-membered macrocycle associated by intermolecular C S⋯O non-bonded weak interactions. The geometry about each tin atom involved is distorted trigonal bipyramidal.
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solvothermal synthesis and crystal structure of a mixed tri and Dimethyltin coordination polymer me3sn μ2 oh me2sn μ3 sch2co2 n
Journal of Organometallic Chemistry, 2006Co-Authors: Rufen Zhang, Qingfu Zhang, Yang ShiAbstract:A mixed tri- and Dimethyltin coordination polymer, {[(Me 3 Sn)(μ 2 -OH)][Me 2 Sn(μ 3 -SCH 2 CO 2 )]} ( 1 ), has been solvothermally synthesized and structurally characterized by elemental analysis, FT-IR, NMR ( 1 H, 13 C, 119 Sn) spectra and X-ray crystallography. This complex displays a 1D helical chain structure, in which it can be considered as the tri- and Dimethyltin moieties are linked together by the alternate μ 2 -OH groups and [μ 3 -SCH 2 CO 2 ] 2− units along the [ 1 0 1 ¯ ] direction. Furthermore, these helical chains are linked together through inter-helix O–H⋯S H-bonding interactions to form a 2D corrugated sheet.
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syntheses and crystal structures of Dimethyltin iv derivatives with 2 6 pyridinedicarboxylic acid
Inorganica Chimica Acta, 2005Co-Authors: Rufen Zhang, Daqi WangAbstract:Abstract A novel cyclic Dimethyltin complex [Me2Sn(2,6-pdc)]3 (1) (2,6-pdc = 2,6-pyridinedicarboxylate) was synthesized by the reaction of Dimethyltin (IV) dichloride and 2,6-pyridinedicarboxylate acid in methanol under solvothermal conditions (150 °C). However, under room temperature (25 °C), we obtained a ladder complex [Me2Sn(2,6-pdc)]2(MeOH)2 (2). Characterization of complexes 1 and 2 was achieved using elemental analysis, IR, 1H, 13C and 119Sn NMR spectra and X-ray diffraction. X-ray data of 1 revealed that it was an unusual cyclic complex with a discrete cyclotrinuclear unit, in which the 12-membered cyclic cavity is almost completely planar. X-ray data of 2 showed that it was a ladder complex, in which a crystallizing methanol molecule is found in each formula unit.