111-18-2Relevant academic research and scientific papers
A new class of bolaforms bearing sulfobetaine and cationic heads: Synthesis and aggregation properties
Souirti, Souad,Baboulene, Michel
, p. 883 - 888 (2003)
We describe here a convenient route to a new family of bolaforms bearing sulfobetaine and cationic heads, which could be scaled up for industrial applications. Their aggregation modes were studied by measurement of surface tension and by dynamic light scattering and transmission electronic microscopy methods. Grafting a hydrophobic chain onto the cationic head modifies both the surface properties and aggregation. Compared to conventional bolaforms, the relationship between the length of the spacer and the side-chain and the resultant hydrophobic interactions are at the origin of these novel properties. Various models of these molecular associations were proposed.
Effect of bolaform counterions on the adsorption of sodium dodecyl sulfonate at the air/water interface
Zhao, Jianxi,Yang, Duoping,You, Yi
, p. 583 - 589 (2014)
The effect of quaternary ammonium-based bolaform counterions (Bolan-series where n is the number of carbon atoms between the heads) on the adsorption of sodium dodecyl sulfonate (SDDS) at the air/water interface has been studied using surface tension measurements. The results showed that the Bolan counterions strongly interacted with SDDS even at very low concentrations. This reduced the CMC and C20 in the presence of Bolan counterions. The SDDS packed more tightly at the interface under the inducement of Bolan counterions and thus the occupied area per surfactant molecule decreased. Another bolaform counterion series (Bolanph) with a benzene ring attached on each side of the quaternary ammonium heads could further enhance the interaction with SDDS. This is due to the fact that the attached aromatic rings penetrate into the gaps between the surfactant headgroups, which provide an additional association force besides the electrostatic attractions. The present results suggested an approach to construct gemini-like surfactants depending on the electrostatic attraction between the bolaform counterions and the conventional ionic surfactants or an additional hydrophobic force made by the attached aromatic rings.
Bestimmung der Struktur von Phenylaethinyllithium in Loesung mittels Tieftemperatur-NMR-Spektroskopie
Haessig, Robert,Seebach, Dieter
, p. 2269 - 2273 (1983)
The dimeric and tetrameric structures of complexes of phenylethinyllithium, as recently discovered by X-ray analysis in the solid state, were also found to be present in solution.Tetrahydrofuran solutions of 1-(6Li)--2-phenylethyne in the presence or absence of N,N,N',N'-tetramethylpolymethylenediamines show a pentuplett 13C-NMR signal from the labelled C-atom at low temperatures (-95 to -110 deg C).This proves the dimeric structure.When (6Li)BuLi is added, a mixed dimer CLi)(C4H9Li)> is formed .This is converted to a mixed tetramer CLi)(C4H9Li)3> upon addition of larger amounts of (6Li)BuLi, as concluded from a signal at δ=133.5 ppm, J(C,Li)=5.6 Hz.The multiplicity of this signal suggests that a static tetramer is present, in which the C-atoms couple only with three next Li-neighbors.
Selective Synthesis of Bisdimethylamine Derivatives from Diols and an Aqueous Solution of Dimethylamine through Iridium-Catalyzed Borrowing Hydrogen Pathway
Fujita, Ken-ichi,Jeong, Jaeyoung
, (2021/12/13)
Bisdimethylamine derivatives are an important class of compounds in the polymer and pharmaceutical industries. However, existing methods for the synthesis of these compounds have several drawbacks such as low selectivity, use of toxic reagents, and generation of waste. In this study, a new system was developed for the selective synthesis of bisdimethylamine derivatives using a diol and dimethylamine as starting materials and an iridium complex bearing an N-heterocyclic carbene ligand as catalyst. The starting materials were easily available, less toxic, inexpensive, and easy to handle. The reaction proceeded efficiently through a borrowing hydrogen pathway under aqueous conditions, without any additional organic solvent, to afford various bisdimethylamine derivatives in good to excellent yields.
Method for synthesizing methylated aliphatic amine compound
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Paragraph 0053; 0054; 0055; 0056; 0057, (2019/03/26)
The invention discloses a method for synthesizing a methylated aliphatic amine compound. A commercially available or easily synthesized aliphatic amine, adopted as a raw material, is subjected to a methylation reaction with methanol to obtain the methylated aliphatic amine compound. The reaction is performed in the presence of an iridium metal complex and under weak alkaline catalysis conditions,only a N,N-dimethylated product is produced without generation of a monomethyl product so that selectivity is high, produced byproduct is water only so that no harm to the environment is caused, and the atom economy of the reaction is high, and therefore, the method meets the requirements of green chemistry and has a broad development prospect.
Method for homogeneously catalyzing alcohol amination
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Paragraph 0069; 0075-0079, (2019/02/21)
The invention relates to a method for homogeneously catalyzing alcohol amination. The method comprises the following steps: mixing diethylene glycol or 1,6-hexanediol, dimethylamine, a ruthenium metalcatalyst and a non-polar solvent and carrying out homogeneous catalysis reaction; separating. According to the method provided by the invention, under the catalysis of a noble metal (rhodium, ruthenium and iridium) metallic catalyst, the diethylene glycol which has a cheap price and is easy to obtain or the 1,6-hexanediol is directly subjected to the amination by utilizing the dimethylamine through a one-step method; bis(2-dialkylaminoethyl)ether or N,N,N,N-tetramethylhexanediamine is prepared in a high-conversion-rate and high-selectivity manner.
Direct Synthesis of N,N-Dimethylated and β-Methyl N,N-Dimethylated amines from nitriles using methanol: Experimental and computational studies
Paul, Bhaskar,Shee, Sujan,Panja, Dibyajyoti,Chakrabarti, Kaushik,Kundu, Sabuj
, p. 2890 - 2896 (2018/04/14)
Direct and selective synthesis of N,N-dimethylated amines from nitriles using methanol as C1 building blocks is reported using an air- and moisture-stable ruthenium complex. Following this process, various aromatic as well as aliphatic nitriles were converted to the corresponding N-methylated amines. Interestingly, tandem C-methylation as well as N-methylation was achieved by introducing multiple methyl groups. The practical aspect of this process was revealed by preparative-scale reactions with different nitriles and the synthesis of anti-allergic drug "avil". Several kinetic experiments and detailed DFT calculations were carried out to understand the mechanism of this process.
Antibacterial and Antibiofilm Activity of Cationic Small Molecules with Spatial Positioning of Hydrophobicity: An in Vitro and in Vivo Evaluation
Hoque, Jiaul,Konai, Mohini M.,Sequeira, Shanola S.,Samaddar, Sandip,Haldar, Jayanta
, p. 10750 - 10762 (2016/12/16)
More than 80% of the bacterial infections are associated with biofilm formation. To combat infections, amphiphilic small molecules have been developed as promising antibiofilm agents. However, cytotoxicity of such molecules still remains a major problem. Herein we demonstrate a concept in which antibacterial versus cytotoxic activities of cationic small molecules are tuned by spatial positioning of hydrophobic moieties while keeping positive charges constant. Compared to the molecules with more pendent hydrophobicity from positive centers (MIC = 1-4 μg/mL and HC50 = 60-65 μg/mL), molecules with more confined hydrophobicity between two centers show similar antibacterial activity but significantly less toxicity toward human erythrocytes (MIC = 1-4 μg/mL and HC50 = 805-1242 μg/mL). Notably, the optimized molecule is shown to be nontoxic toward human cells (HEK 293) at a concentration at which it eradicates established bacterial biofilms. The molecule is also shown to eradicate preformed bacterial biofilm in vivo in a murine model of superficial skin infection.
Efficient ruthenium-catalyzed N-methylation of amines using methanol
Dang, Tuan Thanh,Ramalingam, Balamurugan,Seayad, Abdul Majeed
, p. 4082 - 4088 (2015/11/11)
An in situ-generated complex from [RuCpCl2]2 and dpePhos ligand is reported as an efficient catalyst in the presence of 5 mol % of LiOtBu for the N-methylation of amines using methanol as the methylating agent at moderate conditions, following hydrogen borrowing strategy. This simple catalyst system provides selective N-monomethylation of substituted primary anilines and sulfonamides as well as N,N dimethylation of primary aliphatic amines in excellent yields at 40-100 °C with good tolerance to reducible functional groups. The catalytic intermediate CpRu(dpePhos)H was isolated and was shown to be active for methylation in the absence of base.
Light-promoted N,N-dimethylation of amine and nitro compound with methanol catalyzed by Pd/TiO2 at room temperature
Zhang, Lina,Zhang, Yan,Deng, Youquan,Shi, Feng
, p. 14514 - 14521 (2015/03/05)
A series of TiO2 supported nano-Pd catalysts (Pd/TiO2) were prepared and used for the N,N-dimethylation of different amines and nitro compounds with methanol under UV irradiation at room temperature. A wide range of N,N-dimethyl amines were one-pot synthesized with up to 98% by applying aliphatic secondary amines, aromatic primary amines, aliphatic primary amines and aromatic nitro compounds as starting materials. It is noteworthy that up to 90% yield of 4-chloro-N,N-dimethylaniline was obtained by adjusting the Pd loadings on the TiO2 and the dehalogenation reaction was inhibited. Finally, a reaction mechanism is discussed, involving PhN = CH2 and PhNHCH3 as reaction intermediates.
