Synthesis of organoaluminum compounds containing a silicon atom in the alkyl chain

1962 ◽  
Vol 11 (2) ◽  
pp. 231-233
Author(s):  
L. I. Zakharkin ◽  
L. A. Savina
Keyword(s):  
Silicon Atom ◽  
Alkyl Chain ◽  
Organoaluminum Compounds

Silicon-29 and carbon-13 NMR spectra of model alkylsilanes of the type (CH3)3-nXnSi(CH2)mH

1979 ◽  
Vol 44 (3) ◽  
pp. 854-865 ◽  
Author(s):  
Jan Schraml ◽  
Václav Chvalovský ◽  
Märt Mägi ◽  
Endel Lippmaa
Keyword(s):  
Chain Length ◽  
Silicon Atom ◽  
Alkyl Chain ◽  
Chemical Shifts ◽  
Alkyl Chain Length ◽  
Minor Role ◽  
Total Charge ◽  
Methyl Group ◽  
Silyl Groups ◽  
A Minor

29Si and 13C NMR chemical shifts are presented for the compounds of the type (CH3)3-nXnSi(CH2)mH with various combinations of substituent X (X = C2H5, OC2H5, OC(O)CH3, and Cl), their number n, and alkyl chain length m (m = 1-5). Silicon-29 chemical shifts are shown to follow general trends of the dependence on the total charge or on the number and nature of the substituents on the silicon atom, the alkyl chain length playing only a minor role. It is demonstrated that the silicon upfield shift due to a γ-methyl group varies between is -0.9 and -1.8 ppm in the compounds, the silicon atom of which bears only one secondary carbon atom. The 13C chemical shifts also follow the general dependence on the total charge. In the trimethylsilyl derivatives methylene carbon chemical shifts correlate with the corresponding shifts in carbon analogues and with those in hydrocarbons in which the trimethylsilyl group is replaced by a methyl group. For the short alkyls (m = 1-3) the substituent chemical shifts of various silyl groups depend on the alkyl chain length, α and β effects seem to depend on the number and nature of the substituents on the silicon atom.

Template mediated crystal engineering

1994 ◽  
Vol 52 ◽  
pp. 480-481
Author(s):  
Brigid R. Heywood ◽  
S. Champ
Keyword(s):  
Crystal Engineering ◽  
Electrostatic Interactions ◽  
Alkyl Chain ◽  
Crystallographic Axis ◽  
Two Dimensional ◽  
Engineering Process ◽  
Solution Interface ◽  
Extensive Program ◽  
Geometric Homology ◽  
Long Alkyl Chain

Recent work on the crystallisation of inorganic crystals under compressed monomolecular surfactant films has shown that two dimensional templates can be used to promote the oriented nucleation of solids. When a suitable long alkyl chain surfactant is cast on the crystallisation media a monodispersied population of crystals forms exclusively at the monolayer/solution interface. Each crystal is aligned with a specific crystallographic axis perpendicular to the plane of the monolayer suggesting that nucleation is facilitated by recognition events between the nascent inorganic solid and the organic template.For example, monolayers of the long alkyl chain surfactant, stearic acid will promote the oriented nucleation of the calcium carbonate polymorph, calcite, on the (100) face, whereas compressed monolayers of n-eicosyl sulphate will induce calcite nucleation on the (001) face, (Figure 1 & 2). An extensive program of research has confirmed the general principle that molecular recognition events at the interface (including electrostatic interactions, geometric homology, stereochemical complementarity) can be used to promote the crystal engineering process.

Dispersibility Evaluation of Graphene Oxides with Alkyl Chain Groups by Using Optical Transparency

2015 ◽  
Vol E98.C (2) ◽  
pp. 127-128 ◽  
Author(s):  
Asami OHTAKE ◽  
Seiko UCHINO ◽  
Kunio AKEDO ◽  
Masanao ERA ◽  
Koichi SAKAGUCHI
Keyword(s):  
Alkyl Chain ◽  
Optical Transparency ◽  
Graphene Oxides

Excess molar volumes of binary mixtures of acetic acid and propionic acid with some members of homologous series of alkanes

1991 ◽  
Vol 56 (4) ◽  
pp. 736-744 ◽  
Author(s):  
Ondřej Drábek ◽  
Ivan Cibulka
Keyword(s):  
Acetic Acid ◽  
Propionic Acid ◽  
Alkyl Chain ◽  
Excess Molar Volumes ◽  
Liquid Mixtures ◽  
Entire Concentration Range ◽  
Molar Volumes ◽  
Binary Liquid ◽  
Alkane Molecule ◽  
Increasing Temperature

Excess molar volumes of binary liquid mixtures of (acetic or propionic acid = hexane) at 25 and 35°C, and (acetic or propionic acid + heptane or octane) and (acetic acid + dodecane) at 25°C, measured with a tilting dilution dilatometer, are reported. The excess volumes are positive over the entire concentration range for all mixtures and increase with increasing length of an alkane molecule, decrease with increasing of the alkyl chain in a molecule of carboxylic acid, and increase with increasing temperature.

X-ray Crystallographic Study of Alkylammonium Anthracene-9-carboxylates as a Model for Fibrous Structure of Binary Anthracene Salt Gels

2004 ◽  
Vol 69 (6) ◽  
pp. 1292-1300 ◽  
Author(s):  
Tahahiro Tani ◽  
Kazuki Sada ◽  
Masatsugu Ayabe ◽  
Yuya Iwashita ◽  
Takanori Kishida ◽  
...  
Keyword(s):  
Alkyl Chain ◽  
Columnar Structure ◽  
Hydrogen Bond Network ◽  
One Dimensional ◽  
X Ray ◽  
Crystallographic Study ◽  
Alkylammonium Salts ◽  
Bond Network ◽  
Fibrous Assemblies ◽  
Long Alkyl Chain

Crystal structure of hexylammonium anthracene-9-carboxylate was investigated. The salt was arranged by a one-dimensional hydrogen bond network to form a columnar structure in the crystalline state. This columnar structure should be the model of fibrous assemblies in the organogels of anthracene-9-carboxylate alkylammonium salts having a long alkyl chain.

Alkyl-chain disorder in tetraisohexylammonium bromide

2012 ◽  
Vol 68 (4) ◽  
pp. o152-o155 ◽  
Author(s):  
Malcolm A. Kelland ◽  
Amber L. Thompson
Keyword(s):  
Crystal Structure ◽  
Crystal Growth ◽  
Alkyl Chain ◽  
Growth Inhibitor ◽  
Ammonium Cation ◽  
Asymmetric Unit ◽  
Bromide Anion ◽  
Alkyl Chains ◽  
Hydrate Crystal ◽  
Structure Ii Clathrate Hydrate

Tetraisohexylammonium bromide [systematic name: tetrakis(4-methylpentyl)azanium bromide], C24H52N+·Br−, is a powerful structure II clathrate hydrate crystal-growth inhibitor. The crystal structure, in the space groupP3221, contains one ammonium cation and one bromide anion in the asymmetric unit, both on general positions. At 100 K, the ammonium cation exhibits one ordered isohexyl chain and three disordered isohexyl chains. At 250 K, all four isohexyl chains are disordered. In an effort to reduce the disorder in the alkyl chains, the crystal was thermally cycled, but the disorder remained, indicating that it is dynamic in nature.

High-Performance and Low-Energy Loss Organic Solar Cells with Non-fused Ring Acceptor by Alkyl Chain Engineering

2021 ◽  
pp. 129768
Author(s):  
Dou Luo ◽  
Xue Lai ◽  
Nan Zheng ◽  
Chenghao Duan ◽  
Zhaojin Wang ◽  
...  
Keyword(s):  
Solar Cells ◽  
Energy Loss ◽  
Organic Solar Cells ◽  
High Performance ◽  
Alkyl Chain ◽  
Low Energy ◽  
Fused Ring

scholarly journals Silver Nanoparticles Stabilized with Phosphorus-Containing Heterocyclic Surfactants: Synthesis, Physico-Chemical Properties, and Biological Activity Determination

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1883
Author(s):  
Martin Pisárčik ◽  
Miloš Lukáč ◽  
Josef Jampílek ◽  
František Bilka ◽  
Andrea Bilková ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Biological Activity ◽  
Zeta Potential ◽  
Chain Length ◽  
Alkyl Chain ◽  
Chemical Properties ◽  
Alkyl Chain Length ◽  
Microbial Pathogens ◽  
Physico Chemical ◽  
Phosphorus Containing

Phosphorus-containing heterocyclic cationic surfactants alkyldimethylphenylphospholium bromides with the alkyl chain length 14 to 18 carbon atoms were used for the stabilization of silver nanodispersions. Zeta potential of silver nanodispersions ranges from +35 to +70 mV, which indicates the formation of stable silver nanoparticles (AgNPs). Long-chain heptadecyl and octadecyl homologs of the surfactants series provided the most intensive stabilizing effect to AgNPs, resulting in high positive zeta potential values and smaller diameter of AgNPs in the range 50–60 nm. A comparison with non-heterocyclic alkyltrimethylphosphonium surfactants of the same alkyl chain length showed better stability and more positive zeta potential values for silver nanodispersions stabilized with heterocyclic phospholium surfactants. Investigations of biological activity of phospholium-capped AgNPs are represented by the studies of antimicrobial activity and cytotoxicity. While cytotoxicity results revealed an increased level of HepG2 cell growth inhibition as compared with the cytotoxicity level of silver-free surfactant solutions, no enhanced antimicrobial action of phospholium-capped AgNPs against microbial pathogens was observed. The comparison of cytotoxicity of AgNPs stabilized with various non-heterocyclic ammonium and phosphonium surfactants shows that AgNPs capped with heterocyclic alkyldimethylphenylphospholium and non-heterocyclic triphenyl-substituted phosphonium surfactants have the highest cytotoxicity among silver nanodispersions stabilized by the series of ammonium and phosphonium surfactants.

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