cas 28867-76-7, BENZALDEHYDE AZINE | Articles data

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Kametani et al.
p. 1678
(1960)
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A novel reaction of double carbon - Carbon bond formation: Synthesis of 2,2-dichlorostyrenes
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Shastin,Korotchenko,Nenaidenko,Balenkova
p. 2184 - 2185
(1999)
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Liquid chromatographic determination of hydrazine at sub-parts-per-million levels in workroom air as benzaldazine with the use of chemosorption on benzaldehyde-coated amberlite XAD-2
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Andersson,Hallgren,Levin,Nilsson
p. 1730 - 1731
(1984)
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Small molecular chromogenic sensors for Hg2+: A strong "push-pull" system exists after binding
Two small molecular chromogenic sensors 1 and 2 for detection of Hg 2+ are described. After coordination with Hg2+, a red shift of about 100 nm was observed in the UV/Vis spectra and the color of the solution changed from pale yellow to red which could easily be detected by the naked eye. The results indicate a strong push-pull system was formed after coordination of Hg2+. The 1H NMR spectra and control experiments showed the binding sites of 1 and 2 to be the aniline groups rather than the azine bridge. Moreover, mercury test papers were made by adsorbing 1 onto filter paper, allowing heterogeneous sensing of Hg2+ in aqueous solution. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
Fu, Yanyan,Li, Hongxiang,Hu, Wenping
p. 2459 - 2463
(2007)
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General and Greener Synthesis of Diverse Functional Organic Salts through Schiff Base Chemistry
We report a greener and more-general organic method for the synthesis of functional organic salts containing organic anions through a Schiff base reaction between readily available aldehydes and simple aminoguanidinium salts. This reaction is operationally simple, free of metal salts, and forms water as the sole byproduct. The broad scope and good functional-group compatibility of this method permit its use to provide ready access to a library of more than 70 distinct organic salts, including those of heterocyclic anions, complex pharmaceutical anions, and polyanions, which are difficult to obtain through classical inorganic methods. Moreover, choosing different aldehydes and organic anions provides a convenient method for modulating or improving the functional properties of the designed organic salts, such as their melting points, fluorescence, and energetic properties. We therefore expect that this method will open new opportunities for the discovery and functionalization of a wide variety of organic salts and functional materials.
Hu, Baoping,Shi, Qingrong,Lu, Feipeng,Zhang, Pengcheng,Peng, Panpan,Zhao, Chaofeng,Du, Yao,Su, Hui,Li, Shenghua,Pang, Siping,Nie, Fudie
p. 910 - 918
(2019)
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Spectroscopic and theoretical studies on symmetric aryl azines
Azines, which closely resemble azobenzenes, have important applications in the field of nonlinear optics. NMR and IR spectroscopic study of some symmetric aryl azines has been undertaken with the aid of ab initio theoretical calculations. All data indicated that the structure of azine and substituted azines is the symmetric trans form.
Karthikeyan, Balakrishnan,Jayabharathi, Jayaraman,Thanikachalam, Venugopal
p. 636 - 638
(2007)
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Design, synthesis and biological evaluation of Schiff’s base derivatives as multifunctional agents for the treatment of Alzheimer’s disease
A series of Schiff’s base derivatives was rationally designed, synthesized, and evaluated as multi-function agents for the treatment of Alzheimer’s disease (AD). The results revealed that compound 3b was a novel multifunctional agent. It acted as a highly selective monoamine oxidase-B inhibitor (IC50 = 8.4 nM), which was explained by the docking study. Compound 3b also was an antioxidant agent (2.3 eq) and could significantly inhibit self-induced Aβ1-42 aggregation (31.8%). Meanwhile, compound 3b was a selective metal chelator and could inhibit Cu2+-induced Aβ1-42 aggregation (62.3%). Furthermore, compound 3b presented good neuroprotective effects on H2O2-induced PC12 cell injury. More importantly, compound demonstrated good blood brain barrier permeability and druglike properties. Therefore, compound 3b, a promising multi-targeted active molecule, offers an attractive starting point for further study in the drug-discovery process against AD.[Figure not available: see fulltext.].
Shi, Jian,Zhou, Yi,Wang, Keren,Ma, Qinge,Wei, Rongrui,Li, Qingfeng,Zhao, Yiyang,Qiao, Zhanpin,Liu, Shuang,Leng, Yumin,Liu, Wenmin,Sang, Zhipei
p. 624 - 634
(2020/11/30)

Synthesis of 1,3-dialkyl-4-[(arylmethylidene)amino]glycolurils
[Figure not available: see fulltext.] A method for the synthesis of 1,3-dialkyl-4-[(arylmethylidene)amino]glycolurils was developed based on nucleophilic substitution of the sulfur atom with the oxygen atom in the corresponding thioglycolurils via alkylation of the latter followed by acid hydrolysis of alkylsulfanyl derivatives of thioglycolurils, both with the isolation of alkylsulfanyl intermediates and by the one-pot method. The structure of the synthesized compounds was confirmed by X-ray structural analysis of several examples.
Es’kova, Marina А.,Gazieva, Galina А.,Kolotyrkina, Natalya G.,Kostikova, Natalya N.,Serkov, Sergei А.,Sigay, Natalya V.,Volkhina, Tatyana N.
p. 646 - 655
(2021/07/06)

Dihydrazone-based dynamic covalent epoxy networks with high creep resistance, controlled degradability, and intrinsic antibacterial properties from bioresources
Covalent adaptable networks (CANs) provide a promising approach to solve the issue of recycling thermosets due to their dynamic cross-linked networks. However, CANs are susceptible to creep at relatively low temperatures, and their chemical stability is also inevitably doubtful. Here, we designed novel dihydrazone CANs by cross-linking a dihydrazone-containing epoxy monomer, which was synthesized from the condensation of a lignin derivative vanillin and hydrazinium hydrate, followed by a reaction with epichlorohydrin. Besides the excellent malleability and reprocessability, the dihydrazone CANs exhibited a high initial creep temperature of ～105 °C, which was ascribed to the superior stability of the hydrazone bond at around 100 °C and favorable hydrazone exchangeability at elevated temperatures. Meanwhile, the degradation of the dihydrazone CANs exhibited temperature, solvent, and acidity dependence. Moreover, on account of the high antibacterial properties of the hydrazone bond, the CANs presented a high killing rate (95.8%) for Gram-negative bacteria (E. coli). Thus, this work discloses an effective dynamic covalent motif for the development of CANs with excellent dimensional stability, chemical resistance, and intrinsic antibacterial properties.
Feng, Jie,Li, Qiong,Liu, Yanlin,Lu, Na,Ma, Songqi,Wang, Sheng,Wu, Jiahui,Xu, Xiwei,Yang, Jintao,Zhu, Jin
p. 11261 - 11274
(2020/06/17)

Cp*Co(III)-catalyzed C[sbnd]H amidation of azines with dioxazolones
Cp*Co(III)-catalyzed direct C[sbnd]H amidation of azines has been developed. This conversion could proceed smoothly in the absence of external oxidants, acids or bases, with excellent regioselectivity and broad functional group tolerance. CO2 w
Huang, Yanzhen,Pi, Chao,Tang, Zhen,Wu, Yangjie,Cui, Xiuling
supporting information
p. 3237 - 3240
(2020/09/15)

Ligand Redox-Controlled Tandem Synthesis of Azines from Aromatic Alcohols and Hydrazine in Air: One-Pot Synthesis of Phthalazine
A controlled tandem synthetic route to azines from various alcohols and hydrazine hydrate by the use of a Ni(II) complex of 2,6-bis(phenylazo)pyridine as a catalyst is reported. In marked contrast to the previous report, the reaction is operative using an earth-abundant metal catalyst, milder reaction conditions, and aerobic conditions, which though are desirable but unprecedented in the literature. The catalytic reaction has a vast substrate scope including a single-step synthesis of phthalazine from 1,2-benzenedimethanol and hydrazine hydrate via intramolecular coupling. Mechanistic investigation suggests that the coordinated ligand redox controls the reaction by the use of a reversible azo (N=N)/ hydrazo (NH - NH) redox couple where the metal center is used primarily as a template.
Chakraborty, Mou,Sengupta, Debabrata,Saha, Tanushri,Goswami, Sreebrata
supporting information
p. 7771 - 7778
(2018/06/11)

Selective Reduction of Azines to Benzyl Hydrazones with Sodium Borohydride Catalyzed by Mesoporous Silica-Supported Silver Nanoparticles: A Catalytic Route towards Pyrazole Synthesis
The catalytic activity of supported silver nanoparticles on mesoporous silica was studied, for the selective reduction of azines into benzyl hydrazones using sodium borohydride as mild reducing agent. Different sizes of silver nanoparticles supported on mesoporous silica (Ag/HMS) were successfully prepared by two methods, i.e., wet impregnation followed by reduction with hydrogen at 350 °C and in situ deposition/reduction with a mixture of amines (ethanolamine and ethylenediamine). The Ag/HMS (amines) catalyst was found to promote the selective 1,2-reduction of aryl-substituted azines, compared to the corresponding 1,4-reduction that occurs in general reduction processes. This catalytic transfer hydrogenation process found to be clean, fast and quantitative (>99% yields and selectivity) towards benzyl hydrazone synthesis under mild conditions. Of great importance is that under the present catalytic conditions reducible functional groups remain intact. Formal kinetics, support the in situ formation of silver hydride species being responsible for the reduction process. The presence of protic polar methanol enhanced the catalytic activity of Ag/HMS. Based on the recycling studies the catalytic system Ag/HMS-NaBH4 was found to catalyze the selective reduction of azines nine times without significant loss of its activity. Finally, a one-pot reaction between the in situ produced benzyl hydrazones and a series of nitrostyrenes readily provided the regioselective synthesis of 1,3,5-subtituted pyrazoles, highlighting a useful synthetic application of the catalytic protocol. (Figure presented.).
Charistoudi, Evangelia,Kallitsakis, Michael G.,Charisteidis, Ioannis,Triantafyllidis, Kostas S.,Lykakis, Ioannis N.
supporting information
p. 2949 - 2960
(2017/09/08)

Simple and efficient approach for synthesis of hydrazones from carbonyl compounds and hydrazides catalyzed by meglumine
A simple, environmentally benign protocol for synthesis of hydrazones from carbonyl compounds and hydrazides has been developed in the presence of meglumine in aqueous-ethanol media at room temperature. The salient features of the present protocol are mild reaction conditions, short reaction time, high yields, operational simplicity, metal-free, applicability toward large-scale synthesis, and biodegradable and inexpensive catalyst.
Zhang, Mo,Shang, Ze-Ren,Li, Xiao-Tang,Zhang, Jia-Nan,Wang, Yong,Li, Kang,Li, Yang-Yang,Zhang, Zhan-Hui
p. 178 - 187
(2017/01/10)

Photophysical properties of di-Schiff bases: Evaluating the synergistic effect of non-covalent interactions and alkyl spacers in enhanced emissions of solids
Photophysical properties of di-Schiff base compounds in the solution and solid states are explored. The di-Schiff bases with alkyl spacers (ethyl, butyl and hexyl) showed enhanced light emitting properties in the solid state, while quenching was observed for di-Schiff bases with a hydrazine spacer. The photoluminescence spectra and the crystal structure were compared with bis-pyridyl-ethyl-di-imine and bis-pyridyl-butyl-di-imine. The crystal structure analysis of the compounds rationalizes the observed results. The concentration dependent 1H-NMR and NOESY spectra showed the aggregation behaviour of the compounds.
Das, Moyna,Baig, Fayaz,Sarkar, Madhushree
p. 57780 - 57792
(2016/07/06)

Rhodium(III)-catalyzed coupling of aromatic ketazines or oximes with 2-vinyloxirane via C-H activation
Described herein is a rhodium(III)-catalyzed coupling of aromatic ketazines or oximes with 2-vinyloxirane via directed C-H activation. This reaction proceeds efficiently under mild conditions with a low catalyst loading, especially in conditions with room temperature in the absence of additives for aromatic ketazines. A wide range of substituted substrates is supported and a possible mechanism is proposed according to the experimental results of kinetic isotopic effect, reversibility studies, and catalysis with rhodacycle intermediate c1.
Wen, Jing,Wu, An,Miao, Yuqin,Zhu, Jin
supporting information
p. 5512 - 5516
(2015/09/21)

Solvent-Free Green Synthesis of Azines and Their Conversion to 2,5-Disubstituted-1,3,4-thiadiazoles
A solvent-free, clean, and efficient method has been developed for the synthesis of 2,5-disubstituted-1,3,4-thiadiazoles via azines. This approach exploits the synthetic potential of clean reactions and offers many advantages such as excellent product yie
Shridevi, D. Doddramappa,Ningaiah, Srikantamurthy,Kuduva, Narayan U.,Yhya, Raad K.,Rai, Kuriya M. Lokanatha
supporting information
p. 2869 - 2875
(2015/12/23)

Synthesis, characterization and evaluation of the substituent effect on the amoebicide activity of new hydrazone derivatives
A series of 10 hydrazones were synthesized by condensation of the selected hydrazine and the appropriate aldehyde. After the characterization and electrochemical analysis of each compound, amoebicidal activity was evaluated in vitro against the HM1:IMSS s
Toledano-Maga?a, Yanis,Meléndrez-Luévano, Ruth,Navarro-Olivarria, Marisol,García-Ramos, Juan Carlos,Flores-Alamo, Marcos,Ortiz-Frade, Luis,Ruiz-Azuara, Lena,Cabrera-Vivas, Blanca M.
p. 989 - 996
(2014/07/08)

Initiators based on benzaldoximes: Bimolecular and covalently bound systems
Typical bimolecular photoinitiators (PIs) for radical polymerization of acrylates show only poor photoreactivity because of the undesired effect of back electron transfer. To overcome this limitation, PIs consisting of a benzaldoxime ester and various sensitizers based on aromatic ketones were introduced. The core of the photoinduced reactivity was established by laser flash photolysis, photo-CIDNP, and EPR experiments at short time scales. According to these results, the primarily formed iminyl radicals are not particularly active. The polymerization is predominantly initiated by C-centered radicals. Photo-DSC experiments show reactivities comparable to that of classical monomolecular type I PIs like Darocur 1173.
Griesser, Markus,Rosspeintner, Arnulf,Dworak, Claudia,Hoefer, Michael,Grabner, Gottfried,Liska, Robert,Gescheidt, Georg
p. 8648 - 8657
(2013/01/15)

Highly efficient practical procedure for the synthesis of azine derivatives under solvent-free conditions
A general and useful method for the synthesis of azines of aromatic aldehydes and ketones in good yields was elaborated. This reaction is carried out under solvent-free conditions and in the absence of catalyst to afford good yields of the relevant azines. The reaction is also environmentally friendly without the inconvenience of undesired by-products and has advantages over the previously reported methods. Products were characterized by the usual procedures (infrared, 1H NMR, and 13C NMR).
Safari,Gandomi-Ravandi
experimental part
p. 645 - 651
(2011/04/15)

Experimental measurements and theoretical calculations of the chemical shifts and coupling constants of three azines (benzalazine, acetophenoneazine and cinnamaldazine)
Three azines, two of them doubly labeled with 15N, have been studied by multinuclear magnetic resonance in solution and in the solid state. The spectral parameters obtained by iterative analyses have been compared with DFT/B3LYP calculated values (absolute shieldings and coupling constants). The agreement is generally good. Some anomalies have been discussed in relation to the structure of these compounds. Copyright
Silva, Artur M. S.,Sousa, Regina M. S.,Jimeno, Maria Luisa,Blanco, Fernando,Alkorta, Ibon,Elguero, Jose
p. 859 - 864
(2008/12/23)

Purported synthesis of 3,4,7,8-tetraphenyl-1,2,5,6-tetraazocine from benzil and hydrazine: Competing cyclization and carbon-carbon σ-bond scission
The claims that 3,4,7,8-tetraphenyl-1,2,5,6-tetraazocine can be prepared by the thermal condensation of two moles of benzil monohydrazone or of an equimolar mixture of benzil and benzil dihydrazone have been thoroughly reinvestigated. When such thermolyses were conducted in moist air, neither the claimed 3,4,7,8-tetraphenyl-1,2,5,6-tetraazocine nor the precedented isomeric tetraazapentalene derivative was detected. The following products were unambiguously formed from the heating of molten benzil monohydrazone (%): benzil (10), benzaldehyde (10), benzamide (22), benzyl phenyl ketone (19), benzil bis(ketazine) (11), 3,4,5,6-tetraphenylpyridazine (9), benzil benzaldehyde azine (10), and, after column chromatography, 2,4,5-triphenylimidazole (2). This last component had a melting point and the fluorescent properties in UV light attributed by the original investigator to the mistakenly presumed 3,4,7,8-tetraphenyl-1,2,5,6-tetraazocine. Thus, the original claims for the synthesis of such a novel tetraazocine ring or even for the synthesis of the precedented isomeric zwitterionic tetraazapentalene have now been repudiated. The formation of 2,4,5-triphenylimidazole as a side reaction in the thermolysis of benzil monohydrazone can readily be rationalized as arising from benzil, benzaldehyde, and a source of ammonia, namely, benzamide, in the long-known Radziszewski reaction. Corroborating evidence was provided by data from the thermolysis of benzil dihydrazone. In addition, the origin of other side products is explained in terms of other possible condensations. Finally, preliminary experiments on using irreversible dehydrating agents such as titanium(IV) isopropoxide with benzil monohydrazone indicate that 3,4,7,8-tetraphenyl-1,2,5,6-tetraazocine is formed at room temperature as a transitory intermediate, which eliminates dinitrogen to produce 3,4,5,6-tetraphenylpyridazine. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
Eisch, John J.,Chan, Tsz Y.,Gitua, John N.
p. 392 - 397
(2008/09/18)

Rapid, chemoselective and facile synthesis of azines by hydrazine/I2
We report the reaction of hydrazine hydrate with carbonyl compounds in the presence of molecular iodine at 0-10°C, which affords symmetrical azines in excellent yields in 1 to 4 min without any adverse effect on other substituents. The reactions are rapid and chemoselective, afford excellent yields, and have high-purity products. The workup procedure is environmentally benign and does not require solvent extraction. Copyright Taylor & Francis Group, LLC.
Nanjundaswamy,Pasha
p. 3417 - 3420
(2008/02/13)

An Ullmann coupling of aryl iodides and amines using an air-stable diazaphospholane ligand
(Chemical Equation Presented) A copper-based catalytic system, using an air-stable diazaphospholane as the ligand, was developed for an efficient Ullmann reaction between aryl iodides and alkyl or heterocyclic amines.
Yang, Minghua,Liu, Fei
p. 8969 - 8971
(2008/03/27)

Reaction of 2-acetylbenzofuranhydrazone with aromatic aldehydes: Formation of aldzaines and regeneration of 2-acetylbenzofuran
Hydrolytic cleavage of 2-acetylbenzofuranhydrazone under acidic condition with aromatic aldehyde is described. This method of cleavage of C=N bond is shown to serve as a convenient method for the regeneration of ketone from ketohydrazone besides synthesis of aldazines.
Ujjinamatada, Ravi K.,Agasimundin, Yankanagouda S.
p. 540 - 543
(2008/09/18)

Selective protection of carbonyl compounds as azines and their facile regeneration
Carbonyl compounds with freshly prepared hydrazinium formate successfully yielded the corresponding azines in excellent yields. In turn, azines were deprotected to the corresponding carbonyls using triethylammonium chlorochromate chemoselectively. Copyright Taylor & Francis Group, LLC.
Nanjundaswamy,Pasha
p. 3161 - 3165
(2007/10/03)

Synthesis of 1,3,4-thiadiazoles from aldehyde hydrazones
Reaction of p-tolualdehyde hydrazone with disulfur dichloride in the presence of DBU gave 2,5-di (p-tolyl)-1,3,4-thiadiazole (1a) in 54% yield. Phenyldiazomethane also reacted with disulfur dichloride to afford 2,5-diphenyl-1,3,4-thiadiazole (1b) in 80% y
Okuma, Kentaro,Nagakura, Kazuko,Nakajima, Yasutaka,Kubo, Kento,Shioji, Kosei
p. 1929 - 1931
(2007/10/03)

o-Iodoxybenzoic Acid (IBX) as a Viable Reagent in the Manipulation of Nitrogen- and Sulfur-Containing Substrates: Scope, Generality, and Mechanism of IBX-Mediated Amine Oxidations and Dithiane Deprotections
o-Iodoxybenzoic acid (IBX), a highly versatile hypervalent iodine(V) reagent, was found to efficiently mediate the dehydrogenation of amines in addition to facilitating the oxidative cleavage of dithioacetals and dithioketals. Through the development of relevant IBX-based protocols, a plethora of useful synthetic intermediates, including imines, oximes, ketones, and aromatic N-heterocycles, were found to be readily accessible under notably mild conditions. Further investigation of these transformations led to the elucidation of valuable mechanistic details, resulting in the conclusion that they proceed via ionic rather than single electron transfer (SET) pathways.
Nicolaou,Mathison, Casey J. N.,Montagnon, Tamsyn
p. 5192 - 5201
(2007/10/03)

New reactions of IBX: Oxidation of nitrogen- and sulfur-containing substrates to afford useful synthetic intermediates
New reactions for the synthetic toolbox: 2-lodoxybenzoic acid (IBX) was employed to access a diverse array of useful synthetic intermediates. Among other transformations, the developed chemistry converts amines into imines, dithianes into carbonyl groups, N-heterocycles into N-heteroaromatic compounds, and hydroxylamines into oximes in high yields.
Nicolaou,Mathison, Casey J. N.,Montagnon, Tamsyn
p. 4077 - 4082
(2007/10/03)

Unsymmetrical azines via triisopropylsilylhydrazine
Triisopropylsilylhydrazine, (1), easily prepared from anhydrous hydrazine and chlorotriisopropylsilane (TIPSCI), readily converts aldehydes and ketones to their triisopropylsilyl hydrazones (2 (61-85%)). Desilylation of 2 with TBAF in the presence of a se
Justo De Pomar, Jorge C.,Soderquist, John A.
p. 3285 - 3289
(2007/10/03)

Synthesis of bishydrazones (aldazines)
Bishydrazones have been prepared by thermolysis of aldehyde hydrazone under reduced pressure in a sealed tube at 120-30°C. The possible mass spectral fragementation mode of bishydrazones have also been discussed.
Linganna,Rai, K. M. Lokanatha,Shashikanth
p. 1126 - 1128
(2007/10/03)

A mild and catalytic decarboxylation of α-iminoacids by tributyl phosphine
α-Iminoacids, prepared from α-keto acids and primary amines, undergo decarboxylation to the corresponding imines by reaction with a catalytic amount of tributylphosphine. No reaction has been observed with α-keto acids or their phenyl-hydrazone, tosyl-hydrazone or oxime derivatives under the same conditions. However, carboxy-azines react rapidly with tributylphosphine and give the corresponding aldazines quantitatively. The mechanism of this reaction is also discussed.
Barton, Derek H. R.,Taran, Frederic
p. 4777 - 4780
(2007/10/03)

Oxidative Transformations of Aldazines and Ketazines with Organic Peroxyacids
Oxidation of aromatic aldazines and ketazines with various peroxycarboxylic acids was investigated.It was found that one part of azine molecule 2 was converted into carbonyl compound 1 or related acid 3 while the second part was transformed into carboxylic ester 4 related to peroxyacid used as an oxidant.It was revealed that aromatic azines could be used as a source of diazaarylmethanes and mechanisms of reactions studied were postulated. aldazines, carboxylic esters, ketazines, oxidation, peroxycarboxylic acids
Mlochowski, J.,Giurg, M.
p. 2333 - 2342
(2007/10/02)

2,3-Diaza-1,3-dienes (azines) as substrates for the Staudinger reaction. Synthesis and reactivity of N-imino-β-lactams
The reaction of aromatic and aliphatic azines with different ketene precursors, such as the acid chloride/Et3N system, alkoxychromium(0) carbenes, and free diphenyl ketene, gives N-imino-β-lactams in good to excellent yields, with good levels of cis,trans-selectivity. A wide variety of symmetrically-substituted azines derived from aldehydes and ketones are compatible with the Staudinger reaction. Chiral N-imino-β-lactams derived from symmetrically or unsymmetrically (mixed) chiral azines are also obtained in good yields as essentially single enantiomers (de > 95%). Different reaction intermediates, including hemiaminals, oxadiazols, and hydrazides have been isolated. Free diphenyl ketene forms Diels-Alder adducts and N-acylazadienes in addition to the previously reported N-imino-β-lactams. The usual reactivity of the β-lactam ring is modified in N-imino-β-lactams by the presence of the imino group. Thus, β-hydrazonoesters, N-alkylamino-β-lactams, and NH-β-lactams can be efficiently obtained by base-catalyzed 2-azetidinone ring opening, catalytic hydrogenation, and ozonolysis, respectively.
Alcaide,Miranda,Perez-Castells,Polanco,Sierra
p. 8003 - 8010
(2007/10/02)

Studies on the Oxidation of the Azomethine Compounds with 3-Chloroperbenzoic Acid
Oxidation of the azomethine compounds such as Schiff bases and azines having several nucleophilic centers with 3-chloroperbenzoic acid (MCPBA) being an electrophilic oxidant was investigated.From azines 4, bisaldimines 5, 6, and pyridine derived monoaldimines 7, 8, having various substituents on the imine carbon and nitrogen atoms, the products such as nitrones 9, 15, bisoxaziridines 11, 12; acyldiimine 10 and amide 14 were obtained in high yields.The influence of the structure of substrate on the reaction result is discussed.Key words: aldimines, azines, nitrones, oxaziridines
Mlochowski, J.,Abdel-Latif, F. F.,Kubicz, E.,Said, S. B.
p. 711 - 722
(2007/10/02)

Synthesis and Reactions of p-N-Succinimido Benzoic Acid Azide
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Abdel-Hamid, H. A.,Fahmy, A. F. M.,Shiba, S. A.,Hemdan, M. M.
p. 149 - 158
(2007/10/02)

Initial steps in the reductive condensation of trichloromethylarenes with hydroxylamine and hydrazines in pyridine
Data concerning the initial steps in the reductive condensation of trichloromethylarenes with hydroxylamine or hydrazines in pyridine have been obtained.High yields of the products of the reductive condensation obtained even at equimolar ratios of trichloromethylarene with hydroxylamine or hydrazine as well as the formation of unusual products, i.e., 4-pyridylhydrazones of substituted benzaldehydes, have been interpreted as the results of the participation of pyridine in the reaction as a reductive agent. - Key words: trichloromethylarenes, reductive condensation with hydroxylamine or hydrazines, role of pyridine; 4-pyridylhydrazones of substituted benhaldehydes.
Belen'kii, L. I.,Poddubnyi, I. S.,Krayushkin, M. M.
p. 1844 - 1848
(2007/10/02)

OXIDATION OF HYDRAZINES WITH CARBON TETRACHLORIDE
Some hydrazines, especially 1,2-dialkylhydrazines are oxidized to the corresponding diazenes (azo compounds) by carbon tetrachloride presumably via nucleophilic attack by nitrogen on chlorine.Monacylhydrazines are converted to the corresponding diacylhydrazines.
Sun, Han-Li,McNamara, Bruce,Anselme, J. -P.
p. 791 - 794
(2007/10/02)

Formation and Reactivity of ?-Radical Cation Intermediates in the C-C Coupling Reaction of Phenyldiazomethanes by One-Electron Oxidation
One-electron oxidation of phenyldiazomethanes afforded cis-stilbene predominantly.The reaction was independent of the oxidation methods, e.g., electrolysis, copper(II), triarylaminium salts, or photosensitized one-electron oxidtions.The C-C coupling reaction was retarded by introducing α-substituents on phenyldiazomethanes.The ESR spectra of diazoalkane radical cations could be obtained during the electrolysis at low temperature and the resulting spectra revealed their unique electronic structure as ?-radicals for most cases.When a bulky tert-butyl group was substituted, the corresponding ?-radical cation was observed, but the C-C coupling reaction did not occur.The novel HOMO-LUMO switching by one-electron removal from the HOMO ?-orbital of diazomethane is explained by the interaction of phenyl group with the C-N-N ?-radical moiety.The C-C coupling reaction proceeds via facile cycloaddition between the diazomethane and ?-radical cation, and the preferential formation of cis-olefins is based on the secondary orbital interaction between the two phenyl groups.The structure and the stability of radical cation intermediates are rationalized on the basis of ab initio calculations.
Ishiguro, Katsuya,Ikeda, Masatoshi,Sawaki, Yasuhiko
p. 3057 - 3066
(2007/10/02)

CHLOROSULFONATION OF DIARYL AZINES
Benzaldehyde- and o-, m-, p-anisaldehyde azines; thiophene-2-carboxaldehyde, and biphenyl-4-carboxaldehyde azines (1-8) reacted with excess chlorosulfonic acid to give the disulphonyl chlorides (1a-8a).These were condensed with amines and hydrazine to give 27 derivatives, (Table I) for biocidal evaluation.The orientation of sulfonation is discussed in relation to the stereoelectronic factors and the spectral data.Attempted chlorosulfonation of furan-2-carboxaldehyde azine (9) gave an impure product which could not be clearly characterized as the morpholidate derivative.
Cremlyn, Richard J.,Swinbourne, Frederick J.,Graham, Stephen,Cavaleiro, Jose A. S.,Domingues, Fernando J.,Dias, Maribel
p. 57 - 65
(2007/10/02)

Reductive condensation of trichloromethylarenes with hydroxylamine and hydrazines in pyridine
The interaction of trichloromethylarenes with hydroxylamine in pyridine involves the reductive oximation of aryltrichloromethanes. Further transformations of the oximes in the reaction course can result in the formation of nitriles or 3,5-diaryl-1,2,4-oxadiazoles as final products. The conversion depth depends on reaction conditions and structures of trichloromethyl-arenes. When hydrazines used instead of hydroxylamine, respectivebenzaldehyde hydrazones or azines are obtained.
Belen'kii,Brokhovetskii,Krayushkin
p. 447 - 456
(2007/10/02)

Stereoselective Azine Formation in the Decomposition of Phenyldiazomethanes
The bimolecular dimerization of phenyldiazomethane (1) and 1-diazo-1-phenylethane (2) to form the corresponding azines (3 and 4) is stereoselective for the E,Z isomer (>95:5 E,Z:E,E).The E,Z isomer can be isolated from the reaction of 2, and it can be observed but not isolated from the reaction of 1.Both (E,Z)-3 and -4 revert thermally to the more stable E,E isomer.The kinetic parameters of this process were determined for (E,Z)-4: Ea = 22.3 kcal/mol, log A = 11.2.The stereoselectivity is accounted for within the context of the accepted mechanism for azine formation via diazo compound dimerization.
Abelt, Christopher J.,Pleier, Jennifer M.
p. 1795 - 1799
(2007/10/02)

COMPLEXES OF CYCLOMALTOHEPTAOSE WITH AROMATIC DIAZO COMPOUNDS: FORMATION AND REACTIONS
Pyrolysis of the relatively stable, solid complexes of cyclomaltoheptaose (β-cyclodextrin) with phenyldiazomethane, 1-diazo-1-phenylethane, and diazo(diphenyl)methane results in degradation of the labile guests.The host matrix exerts "reaction-vessel" and "shape-selectivity" effects upon the reaction pathways of the guests and derivatives.The carbene insertion reaction with the β-cyclodextrin hydroxyl groups is regioselective.
Abelt, Christopher J.,Lokey, Jonathan S.,Smith, Shelley H.
p. 119 - 130
(2007/10/02)

7-METHYL- AND 7-PHENYLCYCLOHEPTA-1,3,5-TRIENES FROM BENZVALENE VIA 3,3a,4,5,6,6a-HEXAHYDRO-4,5,6-METHENOCYCLOPENTAPYRAZOLES AND TETRACYCLO2,4.03,5>HEPTANES
The addition of benzvalene (1) to diazomethane, diazoethane, 2-diazopropane, phenyldiazomethane, and diphenyldiazomethane afforded the 1-pyrazolines 2a-g in good yields.By means of competition experiments, the relative reactivities of benzvalene (1) and norbornene with regard to diazomethane and 2-diazopropane have been determined.The fact that benzvalene reacts about twice as fast as norbornene with both diazoalkenes cannot be rationalized on the basis of frontier orbital energies.On direct photolysis, the pyrazolines 2a-g were converted into the tetracyclo2,4.03,5>heptanes 4a-g exclusively.These compounds gave the 1,3,5-cycloheptatrienes 5a,b,d,e,g in high yields on treatment with silver ions, thus providing better access to 7,7-dimethyl-(5d) and 7,7-diphenylcycloheptatriene (5g) than before.Surprisingly, the latter compound is in equilibrium with a substantial quantity of the norcaradiene form.The heat of reaction for the rearrangement of 4a to 5a has been determined, which allows to derive the heat of formation of tetracyclo2,4.03,5>heptane (4a).
Christl, Manfred,Brunn, Erich,Roth, Wolfgang R.,Lennartz, Hans-Werner
p. 2905 - 2916
(2007/10/02)

Thiolato dinitrogen (or hydrazido(4-)) complexes, [Ta(SAr)3(THF)]2(μ-N2) (Ar = 2,6-C6H3-i-Pr2, 2,4,6-C6H2-i-Pr3), and phenoxide analogues. Structural comparison of [Ta(S-2,6-C6H3-i-Pr2)3(THF)] 2 ...
Full title: Thiolato dinitrogen (or hydrazido(4-)) complexes, [Ta(SAr)3(THF)]2(μ-N2) (Ar = 2,6-C6H3-i-Pr2, 2,4,6-C6H2-i-Pr3), and phenoxide analogues. Structural comparison of [Ta(S-2,6-C6H3-i-Pr2)3(THF)] 2(μ-N2) and [Ta(O-2,6-C6H3-i-Pr2)3(THF)] 2(μ-N2). [TaCl3(THF)2]2(μ-N2) reacts with 6 equiv of LiDIPP (DIPP = O-2,6-C6H3-i-Pr2) to give [Ta(DIPP)3(THF)]2(μ-N2) (1) in 60% isolated yield. Crystals of [Ta(DIPP)3(THF)]2(μ-N2) belong to the space group C2/c with a = 20.276 (8) A?, b = 16.737 (7) A?, c = 28.227 (19) A?, β = 105.55 (5)°, V = 9228 A?3, and Z = 4. The structure contains a hydrazido(4-) μ-N2 ligand with N-N = 1.32 (1) A?, Ta-N = 1.796 (5) A?, and Ta-N-N = 176.6 (6)°. The μ-N2 ligand is bound to the metal in an equatorial position of a trigonal bipyramid. [Ta(TIPT)3(THF)]2(μ-N2) (3; TIPT = S-2,4,6-C6H2-i-Pr3) and [Ta(DIPT)3(THF)]2(μ-N2) (4; DIPT = S-2,6-C6H3-i-Pr2) can be prepared analogously in high yield. Crystals of [Ta(DIPT)3(THF)]2(μ-N2) (4) belong to the space group Pc21n with a = 13.606 (6) A?, b = 23.096 (9) A?, c = 28.845 (10) A?, V= 9064.5 A?3, and Z = 4. In this relatively poor quality structure N-N = 1.29 (6) A?, Ta-N = 1.90 (6) and 1.72 (6) A?, and Ta-N-N = 166 (5)°. In this case the μ-N2 ligand is bound in an axial position trans to THF in a trigonal-bipyramidal ligand arrangement about each metal. Neither 1 nor 3 can be prepared by treating Ta(CHCMe3)(DIPP)3(THF) or Ta(CHCMe3)(TIPT)3(THF) with benzaldehyde azine. 1 reacts readily with benzaldehyde to give benzaldehyde azine in high yield, while 3 gives only ～25% benzaldehyde azine.
Schrock,Wesolek,Liu,Wallace,Dewan
p. 2050 - 2054
(2008/10/08)

Thermolysis of geminal diazides: a novel route to 1,3,4-oxadiazoles
The geminal diazides ethyl α,α-diazidoacetoacetate and α,α-diazidobenzoylacetate were prepared from the corresponding dibromo precursors by nucleophilic azide displacement.Thermolysis of the diazido compounds led to the formation of 2,5-disubstituted 1,3,4-oxadiazoles in high yield.
Ogilvie, William,Rank, Werner
p. 166 - 169
(2007/10/02)

Studies on Heterocyclic Enamines: New Syntheses of 4H-Pyranes, Pyranopyrazoles and Pyranopyrimidines
The behaviour of several 2-amino-3-cyano-4H-pyran derivatives toward a variety of nucleophilic reagents is reported.
Elnagdi, Mohamed Hilmy,Abdel-Motaleb, Ramadan Maawad,Mustafa, Mona,Zayed, Mohamed Foad,Kamel, Eman Moustafa
p. 1677 - 1682
(2007/10/02)

An Efficient Synthesis of 3-Substituted Pyrazoles by Reaction of γ,γ-Diethoxy-α-Dimethylaminonitriles (Masked β-Oxoaldehyde Equivalents) with Hydrazine Dihydrochloride
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Takahashi, Kazumasa,Urano, Yuko,Ogura, Katsuyuki,Iida, Hirotada
p. 690 - 691
(2007/10/02)

ZEOLITE-CuNaY CATALYZED DECOMPOSITION OF ARYLDIAZOMETHANE
Decomposition of aryldiazomethanes is catalyzed by copper ion-exchanged Y-type zeolite to afford cis-1,2-diarylethylenes in high selectivity.The catalytic activity and selectivity are found to be affected by the exchange level of copper ions in zeolite and the solvent used.
Onaka, Makoto,Kita, Hiroshi,Izumi, Yusuke
p. 1895 - 1898
(2007/10/02)

THE EFFECT OF ARYL SUBSTITUENTS ON ARYLCARBENE REACTIVITY
Substituted (p-MeO, p-Me, H, p-Cl, p-Br, m-Br, m-MeO, 3,4-Cl2, p-CO2Me, m-CN and p-CN) monophenylcarbenes are generated in a binary mixture of substrates (methanol, cis-4-methyl-2-pentene and cyclohexane) and the relative rate of O - H insertion into methanol to stereospecific cyclopropanation of the olefin to C - H insertion into cyclohexane are calculated from the ratios of products and substrates.It is found (i) that the reactivities of the substrates decrease in the order of methanol, olefin and cyclohexane and (ii) that electron-donating substituents generally lead to reaction with the more reactive substrates while the reaction with the less reactive substrates is favoured in the case of electron-withdrawing substituents.These results are interpreted in terms of the change in the electrophilicity of the singlet arylcarbene by the substituents rather than the change in the singlet-triplet equilibrium.
Tomioka, Hideo,Tabayashi, Kazuo,Ozaki, Yasuji,Izawa, Yasuji
p. 1435 - 1440
(2007/10/02)

Nitrogen Bridgehead Compounds; 43. Facile Synthesis of N-Substituted 6,7,8,9-Tetrahydro-4H-pyridopyrimidine-3-carboxamides
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Balogh, Maria,Hermecz, Istvan,Meszaros, Zoltan
p. 582 - 586
(2007/10/02)

Azines from erythro-1,2-Diaryl-2-(2-tosylhydrazino)-ethan-1-ol Derivatives by Acid Treatment
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Rosini, Goffredo,Soverini, Massimo,Ballini, Roberto
p. 909 - 910
(2007/10/02)