Synthesis and Characterization of Poly(p-phenylene ethynylene)s with nitroxyl radical endgroups

2012 ◽  
Vol 1403 ◽  
Author(s):  
Michael Schroeter ◽  
M. Behl ◽  
C. Weder ◽  
A. Lendlein
Keyword(s):  
Nitroxyl Radical ◽  
Coupling Reaction ◽  
Hydroxyl Groups ◽  
Phenylene Ethynylene ◽  
New Approach ◽  
H Nmr ◽  
Sonogashira Coupling Reaction ◽  
Enhanced Conductivity ◽  
Additional Charge

ABSTRACTThe generation of terminal N-Hydroxyl substituents in p-phenylene ethynylene based compounds is presented. P-phenylene ethynylene derivatives were synthesized in a Sonogashira coupling reaction. N-Hydroxyl groups could be introduced by lithiation of iodine moieties and subsequent reaction with the 2-methyl-2-nitrosopropane generated by the cleavage of its dimer. The synthesis by lithiation was found to be more effective compared to the reaction with the Grignard reagent and the chloro-derivative. The resulting compounds were characterized by 1H NMR, UV and PL spectroscopy and were shown to be sensitive towards oxidation. This new approach of introducing additional charge carriers by nitroxyl endgroups might enable conjugated polymers with enhanced conductivity.

Synthesis and Characterization of an Alendronate-Chitosan Conjugate

2011 ◽  
Vol 140 ◽  
pp. 53-57 ◽  
Author(s):  
Xiao Hong Shao ◽  
Ji Qing Xu ◽  
Yan Peng Jiao ◽  
Chang Ren Zhou
Keyword(s):  
Drug Delivery ◽  
Drug Delivery System ◽  
Synthesis And Characterization ◽  
Hydroxyl Groups ◽  
Amino Groups ◽  
H Nmr ◽  
Ft Ir ◽  
Novel Drug Delivery System ◽  
Novel Drug

The biomineral-binding alendronate-chitosan conjugate (Scheme 1) was developed as a novel drug delivery system. Alendronate was conjugated to the hydroxyl groups of chitosan, thereby maintaining the amino groups of chitosan intact. By means of FT-IR and 1H NMR, the characterization was conducted to confirm the successful synthesis of alendronate-chitosan conjugate.

scholarly journals Synthesis and characterization of a new bis-NHC palladium complex and its catalytic activity in the Mizoroki–Heck reaction

2020 ◽  
Vol 44 (11-12) ◽  
pp. 684-688
Author(s):  
Can Feng ◽  
Cheng-xin Liu ◽  
Yu-fang Wang ◽  
Jin Cui ◽  
Ming-jie Zhang
Keyword(s):  
Palladium Complex ◽  
Coupling Reaction ◽  
Aryl Halides ◽  
Heck Coupling ◽  
X Ray ◽  
X Ray Crystallography ◽  
H Nmr ◽  
Excellent Stability ◽  
C Nmr

A new bis- N-heterocyclic carbene palladium complex, (C13H9N2F2)2PdCl2, is synthesized by a three-step reaction and characterized by 1H NMR and 13C NMR spectroscopy as well as by X-ray crystallography. This new bis- N-heterocyclic carbene palladium complex has excellent stability and is capable of efficiently catalyzing the Mizoroki–Heck coupling reaction of aryl halides with acrylates.

scholarly journals Synthesis and Optoelectronic Characterization of Some Star-Shaped Oligomers with Benzene and Triphenylamine Cores

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Teofilia Ivan ◽  
Loredana Vacareanu ◽  
Mircea Grigoras
Keyword(s):  
Electrochemical Polymerization ◽  
Coupling Reaction ◽  
Aromatic Aldehydes ◽  
Thermal Characterization ◽  
Cyclic Voltammograms ◽  
Heck Coupling ◽  
Molecular Glasses ◽  
H Nmr ◽  
Ft Ir

Six star-shaped oligomers containing triphenylamine (D1–D3) and benzene unit (D4–D6) as cores have been synthesized by Wittig condensation or Heck coupling reaction using aromatic aldehydes and triphenylphosphonium salts or aromatic halogenated compounds with vinyl triphenylamine. All oligomers have well-defined molecular structure and high purity. Characterization of the oligomers was made by FT-IR, 1H-NMR spectroscopy, UV-Vis, and fluorescence spectroscopy. The electrochemical behavior was studied by cyclic voltammetry (CV). The cyclic voltammograms have revealed that oligomers undergo quasireversible or irreversible redox processes. The irreversible process is associated with electrochemical polymerization of oligomers by dimerization of unsubstituted triphenylamine groups. Thermal characterization was accomplished by TGA and DSC methods and evidenced that all oligomers were stable materials until 250°C and have formed stable molecular glasses after first heating scan.

scholarly journals Synthesis and Spectroscopic Characterization of Some New Biological Active Azo–Pyrazoline Derivatives

2012 ◽  
Vol 9 (3) ◽  
pp. 1613-1622 ◽  
Author(s):  
Farouq E. Hawaiz ◽  
Mohammad K. Samad
Keyword(s):  
Addition Reaction ◽  
Coupling Reaction ◽  
Spectroscopic Characterization ◽  
Hydroxyl Group ◽  
Significant Activity ◽  
H Nmr ◽  
Ft Ir ◽  
High Yields ◽  
C Nmr

A number of 3-[4-(benzyloxy)-3-(2-Chlorophenylazo)-phenyl]-5-(substituted-phenyl)-1-substituted-2-pyrazolines( 4a-j) and (5a-j) have been synthesized by diazotization of 2-chloroaniline and its coupling reaction with 4-hydroxy acetophenone, followed by benzyloxation of the hydroxyl group to give the substrate [4-benzyloxy-3-(2-chlorophenylazo)-acetophenone (1)].The prepared starting material (1) has been reacted with different substituted benzaldehydes to give a new series of chalcone derivatives 1-[(4-benzyloxy)-3-(2-chloro-phenylazo)-phenyl]-3-(substituted phenyl)-2-propen-1-one (3a-j), in high yields and in a few minutes, and the later compounds were treated with hydrazine hydrate according to Michael addition reaction to afford a new biolological active target compounds (4a-j) and (5a-j). Furthermore, The structures of the newly synthesized compounds were confirmed by FT-IR,13C-NMR,13C-DEPT &1H-NMR spectral data. The chalcone and pyrazoline derivatives were evaluated for their anti bacterial activity againstEscherichia colias gram negative andStaphylococcus aureusas gram positive, the results showed significant activity against both types of bacteria.

Preparation of Novel Liquid Crystal Material with Trifluoromethyl Substitutent

2013 ◽  
Vol 785-786 ◽  
pp. 690-692
Author(s):  
Yong Ming Zhang ◽  
Yi Wei Wang ◽  
Mei Zhang ◽  
Jian Fang Liu ◽  
Jie Si ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Coupling Reaction ◽  
Sonogashira Coupling ◽  
Reaction Conditions ◽  
H Nmr ◽  
Crystal Material ◽  
Liquid Crystal Material ◽  
Display Area ◽  
Sonogashira Coupling Reaction ◽  
Ft Ir

The liquid crystal material with trifluoromethyl substitutent is a very important liquid crystal monomer to combine mixture in the application of display area. In this paper, a kind of liquid crystal material with trifluoromethyl substitutent was synthesized by traditional method of Sonogashira coupling reaction, the reaction mechanism and reaction conditions were then obtained. In addition, the synthesized compound was characterized by FT-IR and1H-NMR to confirm the consistent structure with target compound.

Synthesis and characterization of novel azo-embedded N-confused tetraphenylporphyrin

2009 ◽  
Vol 13 (02) ◽  
pp. 215-222 ◽  
Author(s):  
Motoki Toganoh ◽  
Takayoshi Hihara ◽  
Kentaro Yonekura ◽  
Yuichi Ishikawa ◽  
Hiroyuki Furuta
Keyword(s):  
Absorption Spectrum ◽  
Effective Interaction ◽  
Coupling Reaction ◽  
Crystallographic Analysis ◽  
Synthesis And Characterization ◽  
X Ray ◽  
H Nmr ◽  
Cis Isomer ◽  
C Nmr

A unique class of azo porphyrin, 5,10,15,20-tetraphenyl-21-phenylazo-(2-aza-21-carbaporphyrin 1, in which an azophenyl group is embedded in N -confused porphyrin, was synthesized and characterized by 1 H NMR, 13 C NMR, UV-vis absorption, MS, and X-ray crystallographic analysis. Synthesis of 1 was achieved through a coupling reaction of 21-amino N -confused tetraphenylporphyrin with nitrosobenzene and subsequent deoxygenation of resulting azoxy derivative with a trioxo rhenium(VII) N -fused porphyrinato catalyst. The azo-conjugate molecule was exclusively obtained as a trans-isomer and no isomerization to the cis-isomer was observed under thermal or photoirradiation. The absorption spectrum of 1 shows a moderate red-shift due to the effective interaction between the porphyrinic π-system and the connecting azophenyl group. Upon protonation, this effect is essentially lost as a result of removing degeneracy of LUMO and LUMO+1.

Synthesis and Characterization of Palladium(II) Schiff Base and their Catalytic Activities for Heck Reaction

2012 ◽  
Vol 554-556 ◽  
pp. 736-740 ◽  
Author(s):  
Amalina Mohd Tajuddin ◽  
Hadariah Bahron ◽  
Karimah Kassim ◽  
Wan Nazihah Wan Ibrahim ◽  
Hoong Kun Fun
Keyword(s):  
Schiff Base ◽  
Coupling Reaction ◽  
Spectroscopic Characterization ◽  
Heck Coupling ◽  
Schiff Base Ligands ◽  
H Nmr ◽  
Catalytic Potential ◽  
Physico Chemical ◽  
Ft Ir

The syntheses, physico-chemical and spectroscopic characterization of ovan-type Schiff-base ligands (L1, L2) and their novel mononuclear Pd(II) complexes (PdL1, PdL2) are reported herein. Elemental analysis, FT-IR,1H NMR as well as magnetic susceptibility measurements characterised the compounds. The catalytic potential of the Pd(II) complexes for Heck coupling reaction were investigated and monitored using GC. It was observed that both Pd(II) complexes displayed properties of good catalysts for the reaction, indicated by 100% conversion of the starting materials to the subtituted alkene product after 6 hours of reaction time at 100°C in inert conditions. The catalytic activity was compared with the reaction without Pd(II) complexes.

Synthesis and characterization of a series of 3-methyl-3-{3-[1-methyl-3-aryl-2-triazenyl]propyl}-1-aryl-1-triazenes and related compounds

2006 ◽  
Vol 84 (6) ◽  
pp. 831-842
Author(s):  
Jeff D Clarke ◽  
Shasta L Moser ◽  
Keith Vaughan
Keyword(s):  
Secondary Amine ◽  
Nmr Spectra ◽  
High Resolution Mass Spectrometry ◽  
Coupling Reaction ◽  
H Nmr ◽  
Methylene Groups ◽  
Related Series ◽  
Diazonium Coupling ◽  
Related Compounds

A series of diazonium salts has been coupled to both secondary nitrogen atoms of the bis-secondary amine, N,N′-dimethyl-1,3-propanediamine (MeNHCH2CH2CH2NHMe), to afford the new bistriazene series, the 3-methyl-3-{3-[1-methyl-3-aryl-2-triazenyl]propyl}-1-aryl-1-triazenes (9). These compounds have been fully characterized by IR and NMR spectroscopy, with supporting data from elemental analysis and high-resolution mass spectrometry. A limited number of model compounds in the N,N-dimethyl-N-{3-[1-methyl-3-aryl-2-triazenyl]propyl}amine series (10) have been synthesized to aid in the interpretation of the NMR spectra of the bistriazenes (9). A series of related compounds, the 3-ethyl-3-{(E)-4-[1-ethyl-3-aryl-2-triazenyl]-2-butenyl}-1-aryl-1-triazenes (11), have been synthesized by diazonium coupling with the bis-secondary amine N,N′-diethyl-2-butene-1,4-diamine (15), and the diazonium coupling reaction with trans-N,N′-dimethycyclohexane-1,2-diamine (19) has been used to prepare another related series of bistriazenes, the 3-methyl-3-{2-[1-methyl-3-aryl-2-triazenyl]cyclohexyl}-1-aryl-1-triazenes (12). The 1H NMR spectra of these compounds are complex because of the presence of two chiral centres in the cyclohexanediamine moiety; the diastereotopic protons of the methylene groups in the cyclohexane ring are clearly distinguished in the 500 MHz spectra of these compounds.Key words: triazene, bistriazene, synthesis, nuclear magnetic resonance, propanediamine, 1,4-diamino-2-butene, cyclohexanediamine.

scholarly journals Spectroscopic Characteristics of Dissolved Organic Matter in Afforestation Forest Soil of Miyun District, Beijing

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Shi-Jie Gao ◽  
Chen Zhao ◽  
Zong-Hai Shi ◽  
Jun Zhong ◽  
Jian-Guo Liu ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Microbial Biomass Carbon ◽  
Soil Samples ◽  
Hydroxyl Groups ◽  
H Nmr ◽  
Spectroscopic Characteristics ◽  
Aromatic Components ◽  
A Minor ◽  
Aliphatic Chains

In this study, soil samples collected from different plain afforestation time (1 year, 4 years, 10 years, 15 years, and 20 years) in Miyun were characterized, including total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), available K (K+), microbial biomass carbon (MBC), and dissolved organic carbon (DOC). The DOM in the soil samples with different afforestation time was further characterized via DOC, UV-Visible spectroscopy, excitation-emission matrix (EEM) fluorescence spectroscopy, and1H NMR spectroscopy. The results suggested that the texture of soil sample was sandy. The extracted DOM from soil consisted mainly of aliphatic chains and only a minor aromatic component. It can be included that afforestation can improve the soil quality to some extent, which can be partly reflected from the indexes like TOC, TN, TP, K+, MBC, and DOC. And the characterization of DOM implied that UV humic-like substances were the major fluorophores components in the DOM of the soil samples, which consisted of aliphatic chains and aromatic components with carbonyl, carboxyl, and hydroxyl groups.

Synthesis and Characterization of Novel Polyfluorene Derivatives

2013 ◽  
Vol 815 ◽  
pp. 443-447
Author(s):  
Li Di Zhou ◽  
Xiao Dan Hu ◽  
Shao Hong Wang ◽  
Zhao Xia Hou ◽  
Mei Han Wang
Keyword(s):  
Glass Transition ◽  
Thermal Properties ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Solid State ◽  
Coupling Reaction ◽  
Synthesis And Characterization ◽  
Sonogashira Coupling ◽  
Sonogashira Coupling Reaction

A novel series of copolymers containing fluorene units are synthesized by Sonogashira coupling reaction in mild condition. Benzene, naphthalene and anthracene are co-polymerized with ethynylfluorene, respectively. The structures are confirmed by NMR, Mass, Elemental analysis and GPC. The polymers have good thermal properties with glass-transition temperature of 90-155°C(Tg), and they have bandgaps from 2.21-2.77 eV. The results of photoluminescence in solid state show that introduction of huge chromophore could effectively suppress the formation of aggregates and excimers which typically cause red-shifted or new emission.

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