Synthesis and characterization of tri-titanium(iv)-1,2,3-substituted α-Keggin polyoxotungstates with heteroatoms P and Si. Crystal structure of the dimeric, Ti–O–Ti bridged anhydride form K10H2[α,α-P2W18Ti6O77]·17H2O and confirmation of dimeric forms in aqueous solution by ultracentrifugation molecular weight measurements†

2001 ◽  
pp. 2872-2878 ◽  
Author(s):  
Kenji Nomiya ◽  
Mizuto Takahashi ◽  
Katsunori Ohsawa ◽  
Jason A. Widegren
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
Molecular Weight ◽  
Synthesis And Characterization

Synthesis and characterization of the pentadentate macrobicyclic ligand, 14-thia-1,4,8,11-tetraazabicyclo[9.5.3]nonadecane (L1) and its nickel(II) complexes. X-ray crystal structure of [Ni(L1)(ClO4)](ClO4)·2[Ni(L1)(OH2)](ClO4)2·6H2O

2001 ◽  
Vol 79 (5-6) ◽  
pp. 930-937 ◽  
Author(s):  
Kevin R Coulter ◽  
Alexander McAuley ◽  
Steven Rettig
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
Axial Symmetry ◽  
Synthesis And Characterization ◽  
High Dilution ◽  
Subsequent Reduction ◽  
X Ray ◽  
Frozen Solution ◽  
Reversible Redox

The pentadentate macrobicycle,14-thia-1,4,8,11-tetraazabicyclo[9.5.3]nonadecane (L1), has been synthesized by high dilution cyclization of 1-thia-4,8-diazacyclododecane ([10]aneN2S) (2) with N,N'-bis(α-chloro acetamido) propane (3) and subsequent reduction of the di-oxo intermediate. The structure of the [Ni(L1)(ClO4)](ClO4)·2[Ni(L1)(OH2)](ClO4)2·6H2O complex (monoclinic, P21/c, a = 13.9261(4) Å, b = 30.279(2) Å, c = 17.1248(3) Å, β = 94.5065(3)°) at R = 0.039 (Rw = 0.034) for 911 parameters using 18 266 reflections with I > 3σI has been determined. The ligand adopts a trans-III configuration. The Ni(II) ion is pseudooctahedral with Ni-S = 2.3896(10) Å in [Ni(L1)(ClO4)]+ and 2.4193(10) Å, 2.4225(10) Å, in the two [Ni(L1)(H2O)]2+ cations. Both nickel(II) and nickel(III) complexes are six-coordinate in solution. Oxidation of the [Ni(L1)(OH2)]2+ complex with K2S2O8 in aqueous solution yielded an ESR active Ni(III) species and the frozen solution spectrum displayed axial symmetry with g[Formula: see text] = 2.159 and g|| = 2.024. In CH3CN, the [Ni(L1)(solv)]2+ complex showed two reversible redox waves corresponding to the Ni2+/+ couple at E1/2 = -1.807 V vs. Fc+/0 and Ni3+/2+ couple at E1/2 = 0.715 V vs. Fc+/0.Key words: synthesis, structure, polydentate macrobicycle, nickel(II).

scholarly journals Synthesis and characterization of a new Organic – Inorganic sulfate (C5H6N2O)2[Co(H2O)6]3(SO4)4.2H2O

2014 ◽  
Vol 10 (4) ◽  
pp. 2639-2647
Author(s):  
M. Mathlouthi ◽  
S. Benmansour ◽  
M. Rzaigui ◽  
W. Smirani Sta
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
Three Dimensional ◽  
Synthesis And Characterization ◽  
Hybrid Compound ◽  
Organic Layers ◽  
Triclinic System ◽  
Dimensional Network ◽  
Inorganic Sulfate

crystals of a new hybrid compound, (C5H6N2O)2[Co(H2O)6]3(SO4)4.2H2O, were synthesized in aqueous solution and characterized. This compound crystallizes in the triclinic system with the space group P-1, the unit cell :a=6.632(3) Å, b=11.769(5) Å, c=14.210(6) Å, α=67.86(4)°, β=81.32(4)°, γ=85.18(4)° and V=1015.14(8) Å3 . Its crystal structure can be described as a packing of alternated inorganic and organic layers. The different components are connected by a three-dimensional network of O-H…O and N-H…O hydrogen bonds. 

scholarly journals Synthesis and characterization of different soybean oil-based polyols with fatty alcohol and aromatic alcohol

e-Polymers ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 491-499
Author(s):  
Fukai Yang ◽  
Hao Yu ◽  
Yuyuan Deng ◽  
Xinyu Xu
Keyword(s):  
Molecular Weight ◽  
Soybean Oil ◽  
Retention Time ◽  
Ring Opening ◽  
Isoamyl Alcohol ◽  
Synthesis And Characterization ◽  
Intermolecular Force ◽  
H Nmr ◽  
Epoxy Groups

Abstract In this article, five kinds of soybean oil-based polyols (polyol-E, polyol-P, polyol-I, polyol-B, and polyol-M) were prepared by ring-opening the epoxy groups in epoxidized soybean oil (ESO) with ethyl alcohol, 1-pentanol, isoamyl alcohol, p-tert-butylphenol, and 4-methoxyphenol in the presence of tetrafluoroboric acid as the catalyst. The SOPs were characterized by FTIR, 1H NMR, GPC, viscosity, and hydroxyl numbers. Compared with ESO, the retention time of SOPs is shortened, indicating that the molecular weight of SOPs is increased. The structure of different monomers can significantly affect the hydroxyl numbers of SOPs. Due to the large steric hindrance of isoamyl alcohol, p-hydroxyanisole, and p-tert-butylphenol, SOPs prepared by these three monomers often undergo further dehydration to ether reactions, which consumes the hydroxyl of polyols, thus forming dimers and multimers; therefore, the hydroxyl numbers are much lower than polyol-E and polyol-P. The viscosity of polyol-E and polyol-P is much lower than that of polyol-I, polyol-B, and polyol-M. A longer distance between the molecules and the smaller intermolecular force makes the SOPs dehydrate to ether again. This generates dimer or polymers and makes the viscosity of these SOPs larger, and the molecular weight greatly increases.

Synthesis and characterization of monomeric siloxo palladium(II) complexes: crystal structure of [Pd(tmeda)(C6F5)(OSiPh3)]

2004 ◽  
Vol 689 (11) ◽  
pp. 1872-1875 ◽  
Author(s):  
José Ruiz ◽  
Consuelo Vicente ◽  
Venancio Rodrı́guez ◽  
Natalia Cutillas ◽  
Gregorio López ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Synthesis And Characterization

Synthesis and Characterization of Poly(Aryl Ether Quinoxaline)s with Controlled Molecular Weight

2011 ◽  
Vol 391-392 ◽  
pp. 826-829
Author(s):  
Song Ya Zhang ◽  
Zhong Xiao Li ◽  
Jia Ling Pu
Keyword(s):  
Molecular Weight ◽  
Glass Transition ◽  
Strong Acid ◽  
Decomposition Temperature ◽  
Molar Ratio ◽  
Synthesis And Characterization ◽  
Aryl Ether ◽  
Good Solubility ◽  
Step Procedure

Novel poly(aryl ether quinoxaline)s (PEQs) were prepared via a two-step procedure. First, poly (ether benzil) (PEB) was synthesized by the polycondensation of 4,4’-difluorobenzil and 4,4’-isopropylidenediphenol.Then, PEB was reacted with 1,2-diaminobenzene and 4,4'-oxydibenzene-1,2-diamine to give the PEQs. The molecular weight of the PEQs could be adjusted easily by varying the molar ratio of 1,2-diaminobenzene to 4,4'-oxydibenzene-1,2-diamine. The PEQs exhibited good solubility in common organic solvents such as NMP, DMAc, DMF, cyclohexanone and chloroform. In addition, the PEQs also had high glass transition (Tg) temperatures and good thermal properties, with an initial thermal decomposition temperature above 475 oC and glass transition temperatures above 210 oC. They also exhibited excellent resistance to strong acid and alkali.

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