- Synthesis and properties of novel spirobifluorene-cored dendrimers
-
Two novel spirobifluorene-cored dendrimers containing polyphenylene dendrons with the carbazole (spiro-Cz) and cyano surface groups (spiro-CN) were synthesized and characterized. Both the dendrimers show good solubility in common organic solvents. Spiro-Cz is amorphous even when it is obtained directly from organic solvents and an extremely high glass transition temperature of 332 °C is detected. These dendrimers can be reversibly oxidized and reduced in electrochemical measurements. They are blue fluorescent with small red-shift in solid film absorption and fluorescence spectra. These advantageous merits are suggested to benefit from the combined contribution from the spirobifluorene core and the bulky polyphenylene dendrons. They were used as emitting layer to fabricate organic light-emitting diodes (OLEDs). Deep-blue electroluminescence was obtained for both dendrimers devices.
- Ren, Huicai,Tao, Qian,Gao, Zhanxian,Liu, Di
-
-
Read Online
- Synthesis and luminescent properties of perylene bisimide-cored dendrimers with carbazole surface groups
-
A group of perylene bisimide (PBI) cored dendrimers were designed and synthesized. The polyphenylene dendrons containing carbazole functional groups at periphery were attached to the PBI core with expectation to control the intermolecular interaction and to tune the charge transporting ability of dendrimers. Their photophysical, electrochemical and thermal properties were investigated. The spectral data showed that energy transfer and photoinduced charge transfer coexist between the carbazole peripheries and the PBI core, competing to influence the luminescent properties of these dendrimers. The red OLEDs were fabricated with these dendrimers as non-doped emitting layer by solution method. The dendrimers bearing carbazoles exhibited improved EL performance than those model compounds. The improved charge balance state caused by these carbazole units is suggested to be responsible for the EL performance.
- Ren, Huicai,Li, Jiuyan,Wang, Renjie,Zhang, Ting,Gao, Zhanxian,Liu, Di
-
-
Read Online
- Enabling DPP derivatives to show multistate emission and developing the multifunctional materials by rational branching effect
-
Conventional polycyclic organic molecules exhibit aggregation-caused quenching (ACQ) effect, and some organic molecules with twisted and propeller backbones could be made into aggregation-induced/enhanced emission (AIE/AEE). However, it was interesting but challenging to enable conjugated molecules derived from fused (hetero)cycles with high photo- and thermal-stability to show multistate emission, rather than only dual emission in solution and crystalline states. In the current work, we presented a rational strategy for realizing multistate emission of 1,4-diketo-pyrrolo [3,4-c]pyrrole (DPP) derivatives by employing imidazole as the additional acceptor bridge and constructing the branched DPP-centered molecule with four peripheral donors (triphenylamine). The resulting D?A?D compound (TIDPP) emitted yellow in solution with the fluorescence efficiency of ca. 70%, and its crystalline and amorphous states as well as aqueous suspensions also exhibited impressive fluorescence efficiencies of 40–50%, filling the gap between ACQ and AIE of DPP derivatives. Moreover, aggregation could greatly red-shift emission spectra and significantly enhance the two-photon absorption cross section and excitation fluorescence in the aqueous suspension. TIDPP solid was also found to exhibit the unique mechanochromic blue-shift luminescence and the commendable OFET performance, signifying the existence of aggregation-induced molecular planarization. This work demonstrated that the rational branching effect could manipulate the aggregation emission behaviors and develop the multifunctional materials.
- Zhang, Kai,Zhang, Zhenzhen,Fan, Xiaojing,Tang, Liangliang,Ding, Qi,Yang, Kun,Zhai, Min,Zhang, Haichang,Xue, Shanfeng,Yang, Wenjun
-
-
Read Online
- Oxidation of: O -dioxime by (diacetoxyiodo)benzene: Green and mild access to furoxans
-
Furoxan has been widely used in the field of high energy density materials because of its excellent properties such as high density, high standard enthalpy of formation and high nitrogen content. However, its existing synthesis methods are still restricted by the problems of difficult substrate preparation and manual handling of hazardous reagents. Herein, we disclosed a mild oxidation strategy to efficiently obtain furoxan derivatives starting from readily available o-dioxime substrates. This reaction features high functional group tolerance and easy scale-up, and has excellent regioselectivity for specific nonsymmetric o-dioximes. This method greatly reduces the safety risk and simplifies the operation process, and means that diversified furoxan derivatives can be easily accessed, thus paving the way for the wide application of furoxan derivatives. This journal is
- He, Chunlin,Pang, Siping,Zhang, Qi,Zhang, Xun,Zhao, Cheng
-
supporting information
p. 1489 - 1493
(2022/01/31)
-
- ORGANIC COMPOUNDS AND ORGANIC LIGHT EMITTING DISPLAY DEVICE USING THE SAME
-
The present disclosure relates to an organic compound and an organic light emitting display device using the same wherein the organic compound is represented by Chemical Formula 1 and a display device using the organic compound. The organic compound represented by Chemical Formula 1 has excellent electron transport properties and durability and is used for an electron transport layer of an organic light emitting element, thereby lowering a driving voltage and improving the luminous efficiency and lifetime. (In the above Chemical Formula 1, at least two of X1, X2 and X3 are N, Y1 and Y2 are each independently a substituted or unsubstituted phenylene group or a single bond, at least one of Ar1 and Ar2 is selected from a substituted or unsubstituted triazine group, a functional group represented by Chemical Formula 2 and a functional group represented by Chemical Formula 3.)
- -
-
Paragraph 0131; 0133
(2021/07/02)
-
- Tetraaryl Cyclopentadienones: Experimental and Theoretical Insights into Negative Solvatochromism and Electrochemistry
-
The synthesis of a series of tetraaryl cyclopentadienones comprising different substitution patterns is reported. Their photophysical and electrochemical properties are investigated by UV/Vis spectroscopy and cyclic voltammetry as well as by supporting quantum chemical simulations and reveal a distinct effect of substituents on the redox behavior of the molecules as well as the absorption properties of this class of compounds. While electrochemical data display a shift in reduction potential of up to 200 mV between the differently substituted cyclopentadienones, their photophysical investigations in differently polar solvents suggest a negative solvatochromic effect, although protic solvents induce a bathochromic shift. Crystal structure analyses of some derivatives confirm similarity with related cyclopentadienones while providing insight into intermolecular C–H···O and C–H···π interactions in the solid state.
- Meitinger, Nicolas,Mengele, Alexander K.,Witas, Kamil,Kupfer, Stephan,Rau, Sven,Nauroozi, Djawed
-
p. 6555 - 6562
(2020/10/02)
-
- One-Pot, Two-Step Metal and Acid-Free Synthesis of Trisubstituted Imidazole Derivatives via Oxidation of Internal Alkynes Using an Iodine/DMSO System
-
A one-pot, two-step, simple, efficient and eco-friendly oxidation of internal alkynes as a key step towards the synthesis of 2,4,5-trisubstituted imidazoles, using an inexpensive I2/DMSO system, has been reported. This metal and acid-free synthesis proceeded smoothly to furnish a variety of synthetically useful trisubstituted imidazoles in moderate to excellent yields. In an effort to demonstrate the potential future applications of this system, a double oxidation study was undertaken and the desired trisubstituted imidazoles obtained in good to moderate yields.
- Naidoo, Shivani,Jeena, Vineet
-
p. 1107 - 1113
(2019/01/04)
-
- Silver-Catalyzed Decarboxylative Couplings of Acids and Anhydrides: An Entry to 1,2-Diketones and Aryl-Substituted Ethanes
-
Silver-catalyzed oxidative decarboxylative couplings of carboxylic acids and anhydrides to produce 1,2-diketones and substituted ethanes were developed. This reaction allows the generation of acyl or alkyl radicals by decarboxylation of the corresponding α-keto acids, alkyl acids and anhydrides, which are sequentially coupled to efficiently construct a new C?C bond. This reaction represents a carboxylic acid decarboxylative alternative that employs a radical termination strategy. (Figure presented.).
- Zou, Hua-Xu,Li, Yang,Yang, Yuan,Li, Jin-Heng,Xiang, Jiannan
-
supporting information
p. 1439 - 1443
(2018/02/26)
-
- NaBrO3/bmim[HSO4]: a versatile system for the selective oxidation of 1,2-diols, α-hydroxyketones, and alcohols
-
Abstract: Sodium bromate with bmim[HSO4] has been found to be an excellent oxidizing agent in aqueous medium. NaBrO3:bmim[HSO4] oxidized 1,2-diols, α-hydroxyketones, and alcohols to the corresponding carbonyl compounds in excellent yields. This method offers advantages such as low cost reagents, aqueous reaction conditions, moderate temperatures and short reaction times and hence environmentally benign reaction. Moreover, the ionic liquid bmim[HSO4] could be recycled for at least three times without loss of significant activity. Graphical abstract: [Figure not available: see fulltext.]
- Khurana, Jitender M.,Lumb, Anshika,Chaudhary, Ankita
-
p. 381 - 386
(2017/02/10)
-
- Synthesis of smart bimetallic nano-Cu/Ag@SiO2 for clean oxidation of alcohols
-
Here, we have demonstrated the synthesis and characterization of silica supported bimetallic copper/silver nanoparticles (Cu/Ag@SiO2 NPs) and their application in the clean oxidation of benzoins/benzyl alcohols in the presence of tert-butyl hydroperoxide as a mild oxidant. All the reactions were very fast (4 h) and high yielding (95-99%), and the Cu/Ag@SiO2 NPs were very stable under the reaction conditions. The catalyst was recovered simply by filtration and reused eight times without loss of its catalytic performance.
- Saha, Arijit,Payra, Soumen,Banerjee, Subhash
-
p. 13377 - 13381
(2017/11/27)
-
- Copper-catalyzed TEMPO oxidative cleavage of 1,3-diketones and β-keto esters for the synthesis of 1,2-diketones and α-keto esters
-
A copper-catalyzed efficient and practical method has been developed for the synthesis of 1,2-diketones and α-keto esters. TEMPO was used as a radical initiator and scavenger, oxidizing the cleavage of α-methylene of 1,3-diketones and β-keto esters to form 1,2-diketones and α-keto esters. This method provided a general way for the formation of 1,2-dicarbonyl compounds.
- Zhou, Peng-Jun,Li, Cheng-Kun,Zhou, Shao-Fang,Shoberu, Adedamola,Zou, Jian-Ping
-
p. 2629 - 2637
(2017/04/03)
-
- A Large π-Extended Carbon Nanoring Based on Nanographene Units: Bottom-Up Synthesis, Photophysical Properties, and Selective Complexation with Fullerene C70
-
Herein we report the organoplatinum-mediated bottom-up synthesis, characterization, and properties of a novel large π-extended carbon nanoring based on a nanographene hexa-peri-hexabenzocoronene (HBC) building unit. This tubular structure can be considered as an example of the longitudinal extension of the cycloparaphenylene scaffold to form a large π-extended carbon nanotube (CNT) segment. The cyclic tetramer of a tetramesityl HBC ([4]CHBC) was synthesized by the reaction of a 2,11-diborylated hexa-peri-hexabenzocoronene with a platinum complex, followed by reductive elimination. The structure of this tubular molecule was further confirmed by physical characterization. Theoretical calculations indicate that the strain energy of this nanoring is as high as 49.18 kcal mol?1. The selective supramolecular host–guest interaction between [4]CHBC and C70was also investigated.
- Lu, Dapeng,Zhuang, Guilin,Wu, Haotian,Wang, Song,Yang, Shangfeng,Du, Pingwu
-
supporting information
p. 158 - 162
(2016/12/30)
-
- COMPOSITION
-
Provided is a composition which comprises two immiscible compounds and a compatibiliser, which stabilises the interface between two or more immiscible compounds. The compatibiliser improves the morphology of blends comprising the first and second compounds. The composition may be useful in the context of functional blends for optoelectronic applications, such as solar cells, organic light-emitting diodes (OLEDs) and organic photovoltaics (OPVs). Also provided is a process for the preparation of the composition and compounds for use therein.
- -
-
Page/Page column 22
(2016/12/22)
-
- Reaction control in heterogeneous catalysis using montmorillonite: Switching between acid-catalysed and red-ox processes
-
The use of montmorillonite, modified with a super-acid (CF3SO3H), in the presence of hydroquinone as a radical scavenger and under a nitrogen atmosphere, induced the formation of tetrasubstituted furans as the major product from benzoins. In the absence of a radical scavenger, the only products obtained were 1,2-diketones.
- Morales-Serna, José Antonio,Frontana-Uribe, Bernardo A.,Olguín, Rosario,Gómez-Vidales, Virginia,Lomas-Romero, Leticia,Garcia-Ríos, Erendira,Gavi?o, Ruben,Cárdenas, Jorge
-
p. 42613 - 42617
(2016/05/19)
-
- Preparation method of 1,2-diketone derivative
-
The invention discloses a preparation method of a 1,2-diketone derivative. The method comprises the step of enabling a raw material 1,3-diketone derivative to react with a cheap and easily obtained industrial product 2,2,6,6-tetramethyl-1-piperidinyloxy under the catalysis of copper so as to obtain the product 1,2-diketone derivative. According to the preparation method, the 1,3-diketone derivative is used as an initiator, and the raw material is easy to obtain and wide in variety; by utilizing the preparation method, the obtained product types are varied, can be directly used, and can be used for other further reactions; in addition, the reagent dosage in the reaction is less, the pollution is reduced, and the production cost is lowered; moreover the reaction conditions are mild, the reaction operation and the after-treatment process are simple, the reaction time is short, the yield is high, and the preparation method is suitable for industrial production.
- -
-
Paragraph 0025
(2016/10/08)
-
- A cycloparaphenylene nanoring with graphenic hexabenzocoronene sidewalls
-
Herein we report the synthesis of a novel hexabenzocoronene-containing cycloparaphenylene carbon nanoring, cyclo[12]-paraphenylene[2]-2,11-hexabenzocoronenylene, by metal-mediated cross-coupling reactions. The nanoring was accomplished by rationally designed palladium-catalyzed coupling of diborylhexabenzocoronene and L-shaped cyclohexane units, followed by nickel-mediated C-Br/C-Br coupling and the aromatization of cyclohexane moieties. The structure was confirmed by NMR and HR-MS. Especially, the cycloparaphenylene structure is firstly observed by STM. The photophysical properties were studied using UV-Vis spectroscopy, photoluminescence (PL) spectroscopy, and theoretical calculations.
- Lu, Dapeng,Wu, Haotian,Dai, Yafei,Shi, Hong,Shao, Xiang,Yang, Shangfeng,Yang, Jinlong,Du, Pingwu
-
supporting information
p. 7164 - 7167
(2016/06/09)
-
- Synthesis of ferrocene derivatives with planar chirality via palladium-catalyzed enantioselective C-H bond activation
-
The first catalytic and enantioselective C-H direct acylation of ferrocene derivatives has been developed. A series of 2-acyl-1-dimethylaminomethylferrocenes with planar chirality were provided under highly efficient and concise one-pot conditions with up to 85% yield and 98% ee. The products obtained could be easily converted to various chiral ligands via diverse transformations.
- Pi, Chao,Cui, Xiuling,Liu, Xiuyan,Guo, Mengxing,Zhang, Hanyu,Wu, Yangjie
-
supporting information
p. 5164 - 5167
(2014/12/11)
-
- N-Heterocyclic carbene-catalyzed double acylation of enones with benzils
-
Thiazolium carbene-catalyzed reaction of aromatic 1,2-diketones with enones in aprotic solvents gave double acylation products in good yields, whereas hydroacylation products formed by Stetter reaction were not detected at all. These results suggested the generation of aroyloxyenamine species from the 1,2-diketones instead of hydroxyenamines (Breslow intermediates). This journal is
- Takaki, Ken,Ohno, Akira,Hino, Makoto,Shitaoka, Takashi,Komeyama, Kimihiro,Yoshida, Hiroto
-
supporting information
p. 12285 - 12288
(2014/12/11)
-
- Unexpected transformation of aldehydes into benzoins with Copper(I)/Samarium
-
The reductive coupling of aldehydes to afford pinacolic alcohols using all kinds of reducing agents involving samarium is well known. In this report, however, treatment of aromatic aldehydes with Cu(I)/Sm system produces benoins and/or benzils in good yields. A possible mechanism is proposed where Cu(I) not only activates the Sm metal but also promotes the dehydrogenation of the intermediates, during which a Cu(III) species may be involved. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications for the following free supplemental resource(s): Full experimental and spectral details.]
- Liu, Yongjun,Wang, Hui,Fu, Yulong,Qi, Yan,Yang, Kuiwei
-
p. 259 - 266
(2013/12/04)
-
- CuI-catalyzed and air promoted oxidative cyclization for one-pot synthesis of polyarylated oxazoles
-
A facile CuI-catalyzed and air promoted oxidative cyclization was developed for the synthesis of polyarylated oxazoles. By virtue of this method, a variety of arylated oxazoles could be easily synthesized from readily available starting materials at room temperature in air. The Royal Society of Chemistry 2013.
- Hu, Ping,Wang, Qiang,Yan, Yizhe,Zhang, Shuai,Zhang, Baiqun,Wang, Zhiyong
-
supporting information
p. 4304 - 4307
(2013/08/23)
-
- N-heterocyclic carbene-catalyzed annulation of α-cyano-1,4-diketones with ynals
-
In this paper, the first stereoselective annulation reaction between r-cyano-1,4-diketones and ynals, mediated by catalytic amounts of a triazolium salt precatalyst and cocatalytic amounts of a weak carboxylate base, is disclosed. The title transformation proceeds smoothly under mild reaction conditions and generates three contiguous stereogenic centers, one of which is a quaternary acetal carbon. This reaction tolerates a wide variety of electronically distinct substituents on both reaction partners and affords privileged bicyclic scaffolds in 61-90% isolated yields and with up to 20:1 diastereomeric preference.
- Romanov-Michailidis, Fedor,Besnard, Celine,Alexakis, Alexandre
-
supporting information
p. 4906 - 4909,4
(2012/12/12)
-
- N-heterocyclic carbene-catalyzed annulation of α-cyano-1,4-diketones with ynals
-
In this paper, the first stereoselective annulation reaction between r-cyano-1,4-diketones and ynals, mediated by catalytic amounts of a triazolium salt precatalyst and cocatalytic amounts of a weak carboxylate base, is disclosed. The title transformation proceeds smoothly under mild reaction conditions and generates three contiguous stereogenic centers, one of which is a quaternary acetal carbon. This reaction tolerates a wide variety of electronically distinct substituents on both reaction partners and affords privileged bicyclic scaffolds in 61-90% isolated yields and with up to 20:1 diastereomeric preference.
- Romanov-Michailidis, Fedor,Besnard, Céline,Alexakis, Alexandre
-
supporting information
p. 4906 - 4909
(2013/01/15)
-
- Metal-free oxidation of α-hydroxy ketones to 1,2-diketones catalyzed by mesoporous carbon nitride with visible light
-
As a photocatalyst, mesoporous carbon nitride (mpg-C3N 4) shows higher photocatalytic activities in organic synthesis. Herein we report an mpg-C3N4-catalyzed oxidation of α-hydroxy ketones to synthesize 1,2-diketones using visible light. This transformation represents a green and highly efficient synthetic route to synthesize 1,2-diketones for which catalytic approaches are scarce.
- Zheng, Zhishuo,Zhou, Xiaosong
-
p. 1683 - 1686,4
(2020/08/31)
-
- N-heterocyclic carbene catalyzed one-pot synthesis of 2,3- diarylquinoxalines
-
A one-pot efficient and facile protocol for the direct synthesis of quinoxaline derivatives via tandem N-heterocyclic carbene (NHC)-catalyzed umpolung of aldehydes/oxidation of the benzoins to benzils/condensation of benzils with benzene-1,2-diamines has been developed. Georg Thieme Verlag Stuttgart New York.
- Lin, Yang,Lei, Xiaoli,Yang, Qin,Yuan, Jiangjun,Ding, Qiuping,Xu, Jingshi,Peng, Yiyuan
-
supporting information
p. 2699 - 2706
(2012/11/13)
-
- Synthesis and properties of novel perylenebisimide-cored dendrimers
-
A group of perylenebisimide-cored dendrimers with polyphenylene dendrons at four bay positions were synthesized and characterized. The electron-deficient pentafluorophenyl or cyano groups were grafted at the dendrimer surface with the aim to further increase the n-type features of the resulted dendrimers. The electrochemical and optical properties were investigated. All the dendrimers show good solubility and film-forming properties, high EA values of 3.8-3.9 eV, and high fluorescent quantum yields. All these merits indicate that they are potential multifunctional materials for application in optoelectronic devices such as solar cells or organic light-emitting devices.
- Ren, Huicai,Li, Jiuyan,Zhang, Ting,Wang, Renjie,Gao, Zhanxian,Liu, Di
-
experimental part
p. 298 - 303
(2012/07/14)
-
- Zinc-catalyzed aerobic oxidation of benzoins and its extension to enantioselective oxidation
-
Zn(II)-DABCO complex is used as an efficient catalyst for the aerobic oxidation of benzoins to benzils in the presence of molecular oxygen. Usage of chiral zinc complex as catalyst resulted in enantioselective oxidative kinetic resolution of racemic benzoin to yield enantiomerically enriched benzoins.
- Muthupandi, Pandi,Sekar, Govindasamy
-
supporting information; experimental part
p. 692 - 695
(2011/03/21)
-
- One-pot synthesis benzils from aldehydes via nhc-catalyzed benzoin dimerization under metal-free conditions in water
-
A simple and convenient one-pot procedure is reported for the synthesis of 1,2-diketones from corresponding benzoin-type condensation reaction of aromatic aldehydes in water with N,N-dialkylbenzimidazolium salt as condensation catalyst and air as oxidizing reagent.
- Bi, Xiaoxin,Wu, Lintao,Yan, Chaoguo,Jing, Xiaobi,Zhu, Hongxiang
-
scheme or table
p. 663 - 664
(2012/02/02)
-
- A new organic transformation by introducing crotyl/allyltrifluoroborates in cross-coupling reaction with aroyl chlorides
-
Microwave irradiated PdCl2(dtbpf) catalyzed direct cross-coupling reaction of aroyl chlorides with potassium crotyl/ allyltrifluoroborates has been developed. Regioselectivity of the cross-coupling product is varied from crotyltrifluoroborate to allyltrifluoroborate.
- Al-Masum, Mohammad,Liu, Kwei-Yu
-
supporting information; experimental part
p. 5090 - 5093
(2011/10/19)
-
- Chiral Zn-catalyzed aerobic oxidative kinetic resolution of α-hydroxy ketones
-
The aerobic oxidative kinetic resolution of racemic α-hydroxy ketones was accomplished using a chiral Zn-quinine complex as the catalyst in the presence of molecular oxygen. The resulting optimized reaction conditions were applied to resolute different types of racemic α-hydroxy ketones and a maximum of 9.2 selectivity (s) was obtained with 88% ee for the recovered α-hydroxy ketone.
- Muthupandi, Pandi,Sekar, Govindasamy
-
experimental part
p. 512 - 517
(2011/06/17)
-
- Facile route to benzils from aldehydes via NHC-catalyzed benzoin condensation under metal-free conditions
-
A simple and efficient one-pot procedure for the synthesis of α-diketones from aldehydes via benzoin condensation under the influence of a catalytic amount of azolium salt combined with DBU has been developed. Thus, aldehyde was allowed to react with the azolium salt/DBU catalytic system at room temperature, and then the reaction mixture was heated to 70 °C under air atmosphere to afford the corresponding 1,2-diketone in good yield. This would be an efficient alternative method of synthesizing α-diketones from aldehydes under metal-free conditions. Crown Copyright
- Shimakawa, Yuuki,Morikawa, Takashi,Sakaguchi, Satoshi
-
supporting information; experimental part
p. 1786 - 1789
(2010/05/19)
-
- Synthesis and characterization of a novel benziloxime ligand and its iron(III) and nickel(II) complexes
-
The synthesis of a novel benziloxime ligand, 4,4′- dibromobenzilmonoxime (DBBOH) (1) and its complexes [Fe(DBBO)3] (2) and Na[Ni(DBBO)3] (3) are described. The ligand (DBBOH) was prepared in MeOH from the reaction of 4,4′-dibromobenzil with hydroxylamine hydrochloride in the presence of sodium acetate. Reaction of sodium salt of 4,4′-dibromobenzilmonoxime (DBBONa) in MeOH with Fe(NO3) 3.9H2O and Ni(NO3)2.6H2O yielded [Fe(DBBO)3] (2) as yellow and Na[Ni(DBBO)3] (3) as brown precipitates respectively. The ligand, 4,4′-dibromobenzilmonoxime (DBBOH) (1) and its complexes [Fe(DBBO)3] (2) and Na[Ni(DBBO) 3] (3) were characterized by elemental analysis, 1H-NMR and 13C-NMR, IR, and electronic spectral studies. The analysis of IR, 1H-and 13C-NMR spectral data of Fe(III) and Ni(II) complexes suggest that 4,4′-dibromobenzilmonoximate is bonded to iron(III) and nickel(II) ions through the oxygen atom of the carbonyl, and the nitrogen atom of the imine groups. The electronic spectral data of the complexes in CHCl3 are in good agreement with the octahedral coordination of Fe(III) and Ni(II) ions. The ligand field parameters for these complexes, i.e. splitting energy and Racah parameter were calculated to be 21560 cm-1 and 707 cm-1 for [Fe(DBBO)3] (2), 13440 cm-1 and 610 cm-1 forNa[Ni(DBBO)3] (3) respectively.
- Soleimani, Esmaiel
-
experimental part
p. 332 - 337
(2011/04/22)
-
- Novel one-pot procedure for the synthesis of 1,2-diketones
-
A simple and convenient one-pot procedure is reported for the synthesis of 1,2-diketones from corresponding benzoin-type condensation reaction of aromatic aldehydes in water with N,N-dialkylbenzimidazolium salt as condensation catalyst and ferric chloride as oxidizing reagent. Copyright Taylor & Francis Group, LLC.
- Jing, Xiaobi,Pan, Xin,Li, Zhen,Shi, Yaocheng,Yan, Chaoguo
-
experimental part
p. 492 - 496
(2009/06/18)
-
- Oxidative cleavage of vicinal diols: IBX can do what Dess-Martin periodinane (DMP) can
-
A study was conducted to demonstrate the similarity of reactivity between o-iodoxybenzoic acid (IBX), an oxidative agent of vicinal diols and Des-Martin periodinane (DMP). The study examined IBX-mediated oxidative cleavage of tert,tert-1,2-diols and discovered pathways that favored fragmentation of sec,sec-1,2-diols, which produce non-cleavage products. It was observed that IBX can be employed to perform oxidative cleavage of 1,2-diols similar to DMP by simple variation of solvent and temperature. It was also observed that protonation of 10-1-4 species of diols may suppress the nucleophilic attack, leading to the production of ketol to achieve oxidative cleavage of sec,sec-1,2-diols that yield non-cleavage products with IBX in DMSO. TFA was used as a significant source of protons and a better solvent of IBX to conduct protonation of diols. A variety of sec,sec,tert,tert and sec,tert syn-1,2-diols underwent oxidative cleavage effectively, using TFA as a solvent.
- Moorthy, Jarugu Narasimha,Singhal, Nidhi,Senapati, Kalyan
-
p. 767 - 771
(2008/03/27)
-
- Catalytic action of triarylstibanes: Oxidation of benzoins into benzyls using triarylstibanes under an aerobic condition
-
Benzoins are simply oxidized to benzils in excellent yields with a catalytic amount of triarylstibanes under an aerobic condition. This catalytic oxidation is heteroatom-specific in the antimony compound and no reaction take place with other group 15 reagents such as triphenylphosphane, -arsane and -bismuthane. The reaction should involve an oxidation-reduction cycle between stibane Sb(III) and stiborane Sb(V) under air.
- Yasuike, Shuji,Kishi, Yoshihito,Kawara, Shin-Ichiro,Kurita, Jyoji
-
p. 425 - 427
(2007/10/03)
-
- Substituted 5,5′-diphenyl-2-thioxoimidazolidin-4-one as CB 1 cannabinoid receptor ligands: Synthesis and pharmacological evaluation
-
A set of 30 substituted 5,5′-diphenyl-2-thioxoimidazolidin-4-one (thiohydantoins) derivatives was synthesized, and their affinity for the human CB1 cannabinoid receptor has been evaluated. These compounds are derived from the previously described cannabinoid ligands 5,5′- diphenylimidazolidine-2,4-dione (hydantoins). The replacement of the oxygen by a sulfur leads to an increase of the affinity while the function-i.e., inverse agonism-determined by [35S]-GTPγS experiments remains unaffected. Finally, to evaluate the molecular parameters that could influence the affinity of the thiohydantoins, molecular electrostatic potential as well as lipophilicity calculations were undertaken on representative thiohydantoins and hydantoins derivatives. In conclusion, 5,5′-bis-(4-iodophenyl)-3-butyl-2- thioxoimidazolidin-4-one (31) and 3-allyl-5,5′-bis(4-bromophenyl)-2- thioxoimidazolidin-4-one (32) possess the highest affinity for the CB 1 cannabinoid receptor described to date for the hydantoin and thiohydantoins series when compared in a same bioassay.
- Muccioli, Giulio G.,Martin, Diana,Scriba, Gerhard K. E.,Poppitz, Wolfgang,Poupaert, Jacques H.,Wouters, Johan,Lambert, Didier M.
-
p. 2509 - 2517
(2007/10/03)
-
- 1-Benzhydryl-3-phenylurea and 1-benzhydryl-3-phenylthiourea derivatives: New templates among the CB1 cannabinoid receptor inverse agonists
-
New 1-benzhydryl-3-phenylurea derivatives and their 1-benzhydryl-3- phenylthiourea isosteres were synthesized and evaluated for their human CB 1 and CB2 cannabinoid receptor affinity. These compounds proved to be selective CB1 cannabinoid receptor ligands, acting as inverse agonists in a [35S]-GTPγS assay. The affinity of 3,5,5′-triphenylimidazolidine-2,4-dione and 3,5,5′-triphenyl-2- thioxoimidazolidin-4-one derivatives, possessing the 1-benzhydryl-3-phenylurea and 1-benzhydryl-3-phenylthiourea moiety, respectively, was also evaluated. In conclusion, the 1-benzhydryl-3-phenylurea scaffold seems to be a new interesting template of CB1 cannabinoid receptor inverse agonists.
- Muccioli, Giulio G.,Wouters, Johan,Scriba, Gerhard K. E.,Poppitz, Wolfgang,Poupaert, Jacques H.,Lambert, Didier M.
-
p. 7486 - 7490
(2007/10/03)
-
- A novel method of synthesis of 1,2-diketones from 1,2-diols using N-bromosuccinimide
-
A simple and convenient procedure is reported for the synthesis of benzils and aliphatic 1,2-diketones of cyclic and open chain compounds from corresponding hydrobenzoins and 1,2-diols by refluxing with N-bromosuccinimide in carbon tetrachloride in presence or absence of pyridine.
- Khurana, Jitender M.,Kandpal, Bhaskar M.
-
p. 4909 - 4912
(2007/10/03)
-
- Versatile access to benzhydryl-phenylureas through an unexpected rearrangement during microwave-enhanced synthesis of hydantoins
-
(Equation presented) A new access to benzhydryl-phenylureas is described. These new interesting urea derivatives were obtained by reaction of substituted benzils with substituted phenylureas under microwave irradiation. Phenylthiourea, when reacted with benzil, gave 3-phenyl-thiohydantoin. Moreover, benzylurea, as phenethylurea, gave the corresponding 3-substituted hydantoin derivatives, demonstrating that only phenylurea derivatives can result in benzhydryl-phenylureas under the applied conditions. This new reaction proved to be an easy access to substituted 1-benzhydryl-3-phenyl-ureas.
- Muccioli, Giulio G.,Wouters, Johan,Poupaert, Jacques H.,Norberg, Bernadette,Poppitz, Wolfgang,Scriba, Gerhard K. E.,Lambert, Didier M.
-
p. 3599 - 3602
(2007/10/03)
-
- Samarium diiodide promoted formation of 1,2-diketones and 1-acylamido-2-substituted benzimidazoles from N-acylbenzotriazoles
-
N-Acylbenzotriazoles, when treated with samarium diiodide in THF, undergo self-coupling reaction to afford 1,2-diketones in good to excellent yields; while when treated with samarium diiodide in CH3CN, they undergo ring-opening reaction to afford 1-acylamido-2-alkyl (or aryl) benzimidazoles in reasonable to good yields. A plausible mechanism was suggested.
- Wang, Xiaoxia,Zhang, Yongmin
-
p. 4201 - 4207
(2007/10/03)
-
- Polyphenylene oligomers and polymers
-
The present invention refers to aromatic monomers containing at least one cyclopentadienone moiety and at least one acetylene moiety and oligomers, uncured polymers and cured polymers comprising the reaction product thereof.
- -
-
Example 1C(b)
(2008/06/13)
-
- Formation of 1,2-diketones by samarium diiodide promoted reaction of N-acylbenzotriazoles
-
Transformation of N-acylbenzotriazoles 1 into 1,2-diketones 2 in good to excellent yields has been realized by the use of samarium diiodide at room temperature.
- Wang, Xiaoxia,Zhang, Yongmin
-
p. 5431 - 5433
(2007/10/03)
-
- Indium-mediated reductive coupling of acyl cyanides: A convenient synthesis of 1,2-diketones
-
The indium-mediated reductive coupling of acyl cyanides afforded the corresponding 1,2-diketones in moderate to good yields under neutral and mild conditions. (C) 2000 Elsevier Science Ltd.
- Baek,Lee,Yoo,Ko,Kim,Kim
-
p. 8097 - 8099
(2007/10/03)
-
- Synthesis of new aryl and hetaryl dibromides and diiodides, the monomers for preparation of polyarylene ethynylenes
-
Dibromides and diiodides with quinoxaline, phenylimidazole, and hexa-or pentaphenylarylene fragments were synthesized from dihalotolans obtained from chloral. Oligoarylene ethynylenes were synthesized by the reaction of the monomers with equimolar amounts of diethynyl aromatic compounds in the presence of the Pd11 complex. Oligomers with imidazole and hexa(penta)arylbenzene cycles are soluble in amide organic solvents and their reduced viscosities do not exceed 0.09 dL g-1.
- Rusanov,Keshtov,Begretov,Khotina,Mikitaev
-
p. 1169 - 1175
(2007/10/03)
-
- Oxidation of Aromatic Compounds. IV. Oxidation of Symmetrical Diarylacetylenes in the CF3COOH-CH2Cl2-PbO2 System. A New One-Pot Synthesis of 1,2,3,4-Tetraaryl-2-butene-1,4-diones
-
Oxidation of symmetrical diarylacetylenes in the CF3COOH-CH2Cl2-PbO2 system (0-20 deg C, 1-3 h) yields 1,2,3,4-tetraaryl-2-butene-1,4-diones.According to (1)H NMR and GC-MS data the compounds synthesized have Z configuration.
- Rudenko, A. P.,Vasil'ev, A. V.
-
p. 1360 - 1379
(2007/10/03)
-
- Efficient Oxidation of organic Compounds with Sodium and Silver Bromates NaBrO3, AgBrO3, in Non-Aqueous Solvents in the Presence of Lewis Acids
-
The syntehtic utility of sodium and silver bromates in the presence of Lewis acids as catalysts in organic solvents is described.They are efficient for the oxidation of alcohols, acyloins, and hydroquinones to their corresponding carbonyl compounds.The oxidation coupling of thiols performs well in the absence of the catalysts.Silver bromate is able to transform primary benzylic and saturated alcohols, aldehydes, and primary benzylic carbon-hydrogen bonds to their carboxylic acids efficiently.Secondary benzylic carbon-hydrogen bonds are oxidized to their carbonyl compounds with sodium and silver bromates.
- Firouzabadi, Habib,Mohammadpoor-Baltork, Iraj
-
p. 2319 - 2326
(2007/10/03)
-
- Cobalt catalysed synthesis of 1,2-diones from aromatic aldehydes in the presence of n-butanal
-
Cobalt(II) chloride catalyses the oxidative coupling of a wide range of aromatic aldehydes in the presence of dioxygen to afford 1,2-diones or carboxylic acids. Aromatic aldehydes may be transformed to 1,2-diones in the presence of n-butanal whereas the presence of acetic anhydride and n-butanal lead to the formation of the corresponding carboxylic acids.
- Punniyamurthy,Kalra, Swinder Jeet Singh,Iqbal, Javed
-
p. 2959 - 2960
(2007/10/02)
-
- NEW APPROACHES TO THE SYNTHESIS OF 4,4'-BIS(PHENYLGLYOXALOYL)BENZIL USING OXIDIZING REAGENTS BASED ON DMSO
-
Two new approaches were developed to the synthesis of 4,4'-bis(phenylglyoxaloyl)benzil, involving a combination of styrylation and ethynylation of substituted bromo- and iodoarenes and oxidation of the intermediate products with HBr/DMSO and I2/DMSO.
- Yusubov, M.S.,Filimonov, V.D.,Khlebnikova, I.V.,Vasil'eva, V.P.,Chaikovskii, V.K.
-
p. 1532 - 1535
(2007/10/02)
-
- Chromium(VI) Based Oxidants; IV. Zinc Chlorochromate Nonahydrate as an Efficient and Mild Oxidizing Agent
-
Zinc chlorochromate nonahydrate is an easily prepared and a cheap oxidizing agent for the oxidation of different types of hydroxy compounds, unsaturated hydrocarbons, and benzylic carbon hydrogen bonds at room temperature in dichloromethane.
- Firouzabadi, H.,Sharifi, A.
-
p. 999 - 1002
(2007/10/02)
-
- Air oxidation of p-substituted benzoin to the corresponding benzil catalyzed by Fe(II)-cysteine peptide complexes
-
The Fe(II)-cysteine-containing peptide complexes were found exhibit catalytic activity for air oxidation of benzoin to benzil and methyl DL-mandelate to methyl benzoylformate. In the presence of [Fe(Z-cys-Gly-Val-OMe)4]2-, the rates of catalytic air- oxidation of p-substituted benzoin indicate a trend, Br> H> CH3 > MeO, and the isotope effect kH/kD was 3.4. The indicates that the methine hydrogen of benzoin is released as a proton in the rate determining step. Furthermore, solvent effect was found, in a non-polar solvent, e.g. 1,2-dimethoxyethane (DME), a chelating bidentate cys-peptide complex, [Fe(Z-cys-Pro-Leu-cys-Gly-Val-OMe)2]2-′ shows higher catalytic activity than that of a non-chelating cys-peptide complex, [Fe(Z-cys-Gly-Val-OMe)4]2-. This is explained by the contribution of intramolecular NH---S hydrogen bonds since such hydrogen bonds stabilize the Fe(III) state which is the active species during the oxidation.
- Sun, Wei-Yin,Ueyama, Norikazu,Nakamura, Akira
-
p. 1557 - 1566
(2007/10/02)
-
