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The one- and two-dimensional 15N, 13C and 1H NMR spectra of benzenediazonium chloride coupling product with 3-methylquinoxalin-2(1H)-one were measured and analysed. It was convincingly proved that two components of the reaction product obtained by coupling reaction are 3-[(Z)-(2-phenylhydrazinylidene)methyl]quinoxalin-2(1H)-one ((Z)-1, major component) and 3-[(E)-(2-phenylhydrazinylidene)methyl]quinoxalin-2(1H)-one ((E)-1, minor component). Detailed analysis of 15N, 13C and 1H NMR spectra allowed to correct previously published incorrect data describing a tautomeric equilibrium between azo and hydrazo forms. Multinuclear and multidimensional NMR studies have been proven to be extremely effective in resolving the tautomeric forms of ‘azo’ dye systems.

Development of new derivatives of commercial antibiotics using different organic reagents and testing these derivatives against different microorganisms are the main goals of this article. Thus, the antibiotic ciprofloxacin, CF, was acylated via reaction with ethyl cyanoacetate and ethyl acetoacetate in basic medium to give the cyanoacetylpiprazinyl dihydroquinoline derivative 3, and oxobutanoylpiprazinyl dihydroquinoline derivative 5, respectively. On the other hand, N-alkylated derivatives 8–10, were prepared through the reaction of CF with chloroacetonitrile, chloroacetyl acetone and chloroacetone in the presence of carbonate salt. In basic medium, both 3 and 10 were coupled with benzenediazonium chloride to afford hydrazono derivatives, which were then cyclized to give 4-(dihydropyridazinecarbonyl)piperazinyl-1,4-dihydroquinoline. Furthermore, compounds 3 and 10 were reacted with benylidenemalononitrile to produce 4H-pyan and pyrido[1,2-a]pyrazine derivatives, respectively. Both 3 and 10 were reacted with DMFDMA to give enaminone derivatives. These enaminones were cyclized to aminopyrimidine derivatives by reacting with urea or thiourea. X-ray, elemental analysis and spectral data were used to illustrate and confirm the structures of the isolated compounds. The bioactivities of the novel compounds were investigated against different gram-positive and gram-negative bacteria. In addition, these novel antibiotic derivatives were tested against ciprofloxacin-resistant bacteria isolated from patients aged 65–74 years. This study reveals that most of the modified drugs show high to moderate antibacterial activity. Additionally, these drugs show good effects against ciprofloxacin-resistant bacteria.

There is an immense push for the development of innovative, convenient and high-performance organic electronics. In this study, we present the synthesis of two azines and the exploration of their photophysical, surface morphological, electrochemical and electroluminescence properties for application in organic electronic devices. A diphenol substituted azine, 2,2'-[hydrazine-1,2-diylidenedimethylylidene]diphenol was synthesized by refluxing ethanolic solution of hydrazine hydrate with ethyl 2-oxo-2 H -chromene-3-carboxylate. It was then converted into an azine spacer incorporated new tetrazo dye, bis–[2-(iminomethyl)-4-(phenyl diazenyl)phenol] by coupling with benzenediazonium chloride. The structures of the symmetrical azines were confirmed by FT-IR, NMR and mass spectroscopic techniques. Both the azines in thin film states exhibited deep yellow photoluminescence on UV excitation at 570 nm. The HOMO and LUMO energy levels assessed by cyclic voltammetry measurements, conformed to the electrochemical band gap energies of 4.41–4.55 eV. The p-type conductivity of the azines were confirmed by hot probe technique. The transport properties of both the azines were investigated by fabricating a bi-layer device. The successful construction of diodes with azines suggest that they could play a significant role as organic materials in the construction of electronic devices.

The one- and two-dimensional 15N, 13C and 1H NMR spectra of benzenediazonium chloride coupling product with 4-R-naphthalene-1-ols (R = NO2 (1), Br (2), Cl (3), H (4), OCH3 (5)) were measured and analysed. It was found that the reaction products exist predominantly in hydrazone forms. Contrary to previously published influence of substituents in diazonium salts, where more electron acceptor types of substituents cause increase contents of hydrazo forms, the situation in compounds 1–5 is completely opposite. Moreover, hydrazone content in 4-nitro-2-[(E)-(4-nitro-phenyl)diazenyl]naphtalen-1-ol (6) combining substitution both in position 4 of passive component and position 4 of active component (i. e. diazonium salt) is higher compared with that in 4-nitro-2-[(E)-(phenyl)diazenyl]naphtalen-1-ol (1).

This article describes the synthesis of some novel coumarin compounds to use as acid dyes by using compounds 1 - 4 as starting materials, which were prepared by interaction of 2-hydroxybenzaldehyde with ethyl 3-oxobutanoate, diethylmalonate, 4-nitrobenzenediazonium chloride and 4-sulfobenzenediazonium chloride, respectively. Compound 1 reacted with bromine and 2-cyanoacetohydrazide to give phenacyl bromide derivative 5 and 2-cyanoacetohydrazone derivative 6, respectively. Coupling of compound 6 with equimolar amount of 2-sulfo-4-((4-sulfophenyl) diazenyl)benzenediazonium chloride gave coumarin acid dye 8. Phenacyl bromide derivative 5 re-acted with potassium cyanide in refluxing ethanol to produce compound 7, which on coupling with equimolar amount of 8-hydroxy-6-sulfonaphthalene-2-diazonium chloride and 8-hydroxy-3,6-disulfonaphthalene-1-diazonium chloride gave coumarin acid dyes 9 and 10, respectively. Interaction of compound 2 with 2-amino-5-((4-sulfophenyl)diazenyl)benzenesulfonic acid, benzene-1,4-diamine and 3,3’-dimethoxy-[1,1’-biphenyl]-4,4’-diamine in refluxing ethanol afforded compounds 11, 12 and 14, respectively. Diazonium sulphate of compounds 12 and 14 coupling with 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid gave compounds 13 and 15, respectively. Cyclocondensation of compound 3 with ethyl 3-oxobutanoate, diethyl malonate and malononitrile afforded derivatives of 3-acetyl-2H-chromen-2-one 16, ethyl 2-oxo-2H-chromene-3-carboxylate 17 and 2-imino-2H-chromene-3-carbonitrile 18, respectively. Reaction of sodium benzenesulfonate derivative 4 with ethyl 3-oxobutanoate and hydrazine hydrate gave compounds 19 and 20, respectively. The structures of the newly synthesized compounds were confirmed by elemental analysis, UV/ VIS, IR, 1H NMR and Ms spectral data. The suitability of the prepared dyestuffs for dyeing of wool and silk fabrics has been investigated. The dyed fabric shows good light fastness, very good rubbing, perspiration, washing and excellent sublimation fastness. These dyes have been color shade from blue to violet with very good depth and levelness on fabrics. The dye bath exhaustion and fixation on fabric has been found to be very good.

2-(4-Phenylthiazol-2(3H)-ylidene)-malononitrile was synthesized by treating 1-phenyl-2-thiocyanatoethanone with malononitrile. Reaction of 2-(4-phenylthiazol-2(3H)-ylidene)-malononitrile with hydrazine hydrate afforded 4-(4-phenylthiazol-2-yl)-1H-pyrazole-3,5-diamine, reaction with benzylidenemalononitrile yielded 2-(5-benzylidene-4-phenyl-5H-thiazol-2-ylidene)-malononitrile, and coupling with benzenediazonium chloride gave 2-(4-phenyl-5-phenylazo-3H-thiazol-2-ylidene)-malononitrile. Diaminopyrazole reacted with enaminonitrile to yield the 3-(4-phenylthiazol-2-yl)pyrazolo[1,5-a]pyrimidine-2,7-diamine. All synthesized compounds showed significant antimicrobial activities with MIC range of 5–750 µg/mL. The results demonstrated a correlation of the hydrophobicity of the compounds with their antimicrobial activity. The most potent antimicrobial compound was 2-(4-phenylthiazol-2(3H)-ylidene)-malononitrile.

The mechanism of the compression-induced decomposition of aryl diazonium chlorides is proposed on the basis of quantum-chemical calculations of both the isolated cations and crystalline materials. The electron transfer from the anion to the cation, followed by the crystal decomposition, is observed with the rise of pressure. Taking the known nature of the structural changes in cations undergone upon reduction, five structural, vibrational and electronic determinants of impact sensitivity are found. Thus, a correlation (R2 = 0.79) between the experimentally known impact sensitivity of 40 different aryl diazonium cations and the developed empirical function Ω, which includes the above-mentioned parameters, is obtained. Meanwhile, an abnormal impact sensitivity of 4-nitrobenzenediazonium chloride (4 J) compared to the parent benzenediazonium chloride (3 J) is rationalized on the basis of first-principles calculations of the latter and its three nitro derivatives. Using our recently proposed solid-state criteria of impact sensitivity, another empirical function Ω was developed being able to predict impact sensitivity of these four salts with very good confidence (R2 = 0.97).

Cyclohexane-1,3-dione (1) was used as a template to develop new anticancer compounds. The ring modification of compound 1occurred through its reaction with either aromaticaldehydes or benzenediazonium chloride to produce the corresponding products. The latter compounds underwenttheterocyclization reactions through the reaction with elemental sulfur and some active methylene reagents to produce tetrahydrobenzo[b]thiophene derivatives. The reaction of compound 1 with elemental sulfur and phenylisothiocyanategave the tetrahydrobenzo[d]thiazole derivative. The cytotoxicity of the newly synthesized products against human cancer and normal cell lines was evaluated. Some compounds showed high cytotoxicity against cancer cell lines. The results showed that compounds 3b, 5c, 7b, 10b, 12, 14b, 16, 18b, 19b, 20b, 21 and 24 showed the highest cytotoxicity. Moreover, the toxicity of twelve active compounds were measured.

The reaction between 2-mercapto-3 H -chromeno[4,3- d ]pyrimidine-4,5-dione (1) or its 2-methylthio derivative (7) with hydrazonoyl halides (2) in dioxane under ultrasound irradiation in the presence of chitosan yielded chromeno[4,3- d ][1,2,4]triazolo[4,3- a ]pyrimidine derivatives (5a-r). On the other hand, the reaction of compound 1 with the appropriate active chloromethylene compounds (9b, h and m) followed by coupling the products with benzenediazonium chloride afforded the azo coupling products which converted in situ to compound 5. The reaction mechanism was proposed and the structure of the newly synthesized compounds were established on the basis of spectral data (Mass, IR, 1 H and 13 C NMR) and elemental analyses.

The 4-thiazolidinones 3a–d were used as a key intermediates for the synthesis of 2-arylimino-5-arylidene-4-thiazolidinones derivatives 7a–p via nucleophilic addition reactions with the arylidene malononitrile. Moreover the 4-thiazolidinones 3a and 3c condensed with the DMF-DMA to form the corresponding enamines 8 and 9 depending on the reaction conditions. Otherwise the 4-thiazolidinone 3b reacts regioselectively with DMF-DMA to afford the enaminones 10 and 11, respectively. The latter reacts with many heterocyclic amines affording polyfunctionally substituted fused pyrimidine derivatives 13–18. The enamine 8b was also reacted with the 3-amino-1,2,4-triazole to afford the acyclic product 19, which could not be further cyclized to the corresponding tricyclic system 20. Moreover the 4-thiazolidinone 3c reacted with the benzenediazonium chloride to afford the arylhydrazones 12. The X-ray single crystal technique was employed in this study for structure elucidation and Z/E potential isomerism configuration determination. The X-ray crystallographic analyses of eight products could be obtained, thus establishing with certainty the structures proposed in this work.

The reaction of cyanoacetylhydrazine with chloroacetone gave the N-(1-chloropropan-2-ylidene)-2-cyanoacetohy- drazide. This compound reacted with either hydrazine hydrate or phenylhydrazine to give the corresponding 1,2,4-tri- azine derivatives. On the other hand, its reaction with either benzenediazonium chloride or benzaldehyde gave in each case the 1,3,4-oxadiazine derivatives. Moreover, the reaction of the cyanoacetylhydrazine with 2-boromocyclohexa- none gave the corresponding hydrazine-hydrozon derivative. The antitumor evaluation of the newly synthesized prod- ucts against three cancer cell lines, namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) was recorded. Some of the tested compounds showed activities which was higher than the reference doxorubicin.

The hydrazide-hydrazone 3 reacted with benzenediazonium chloride to give the phenylhydrazone derivative 5. The latter underwent a series of hetero- cyclization reactions to give pyridazine, 1,2,3-triazole and pyrazole derivatives. The antitumor evaluation of the newly synthesized products against the three cancer cells lines namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) showed that some of them have higher inhibitory effects towards the three cell lines compared to the standard. Key word: hydrazide-hydrazone, pyridazine, 1,2,3-triazole, pyrazole, anti-tumor. activities. These observations led us to synthesize novel hydrazide-hydrazones and to investigate their possible antitumor activities. It has been reported in the literature 17,18 that hydrazide-hydrazones can give the corresponding hydrazide and aldehyde metabolites whereas the related hydrazides are known to yield carboxylic acids via hydrolytic route. Based on this knowledge, hydrazide-hydrazones derivative 3 was prepared easily from the reaction of cyanoacetyl hydrazine with benzaldehyde and subsequently used for the synthesis of pyridazine, 1,2,3-triazole and pyrazole derivatives. The newly synthesized compounds were tested to evaluate their in vitro anti-tumor activities against three human tumor cell lines representing different tumor types, namely, breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268). It was found that some of these compounds showed inhibitory effects on the three cell lines, indicating their potential use in the development of anti-cancer agents. group of compound 15 using sodium nitrite solution in the presence of acetic/ hydrochloric acids resulted in the formation of intermediate pyrazole-3- diazonium salt 16. Coupling of the latter diazonium salt with malononitrile in ethanol containing sodium acetate afforded the hydrazo derivative 17. The analytical and spectral data of the obtained product were consistence with the proposed structure (Scheme 2).

Coupling of bis-enaminones with benzenediazonium chloride and 3-diazo-1,2,4-triazole proved to be convenient routes for the synthesis of novel 3,4-bis(pyrazol-3-yl)pyrazoles and 3,6-bis(heteroaryl)pyrazolo[3,4- d]pyridazines which have not been reported previously. The structures of the products were elucidated on the basis of their spectral properties, elemental analyses and, wherever possible, by alternate synthesis.

The solubility, electrical conductivity, and other properties of polyaniline (PANI) are highly dependent on its oxidation state. In this work, polyaniline (PANI1) prepared by peroxodisulphate induced polymerization of aniline in acidic aqueous medium in presence of benzenediazonium chloride salt was found to exist in lower oxidation state than emeraldine form of PANI and was highly soluble in common organic solvents. This polymer was subjected to positron annihilation spectroscopic study to investigate the correlation between the oxidation state of the polymer and defect sites generated by different degrees of protonation that in turn affect its electrical conductivity. The positron annihilation lifetime data were resolved to yield a three-component fit for PANI1 subjected to different levels of protonation. The variation of positron annihilation parameters (τ1,I2) and Doppler broadening parameters (R, S) as a function of protonation level of the polymer indicate the dopant sites increase initially on protonation and reach a saturation value after a certain level of acidification. The lower value of electrical conductivity and the intensity of intermediate lifetime component (I2) for PANI1 compared to PANI in emeraldine oxidation state indicate the presence of lesser number of quinoid–imine moieties that could undergo protonation and thus yield highly enriched trapping centers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The reported structures of reaction products of enaminones with malononitrile in ethanolic piperidine are revised. A novel route to 2,3-dihydropyridazine-4-carboxylic acids 4a-c via reactions of 2-cyano-5-(dimethylamino)-5-arylpenta-2,4-dienamides 8a-c with nitrous acid or with benzenediazonium chloride is reported. Compounds 8a-c are converted to 1,2-dihydropyridine-3-carboxylic acid and 1,2-dihydropyridine-3-carbonitrile derivatives upon reflux in EtOH/ HCl and in AcOH.

The reaction of 2-mercapto-6,7,8,9-tetrahydro-3H-benzo[4,5]thieno[2,3-d]pyrimidin-4-one or its 2-methylthio derivative with hydrazonoyl halides, in the presence of triethylamine, yielded 6,7,8,9-tetrahydrobenzo[4,5]thieno[2,3-d]-1,2,4-triazolo[4,5-a]pyrimidin-5-ones. The structure of the latter compounds was further confirmed by reaction of 2-mercapto-6,7,8,9-tetrahydro-3H-benzo[4,5]thieno[2,3-d]pyrimidin-4-one with the appropriate active chloromethylenes followed by coupling of the products with benzenediazonium chloride to afford the non-isolable azo-coupling products which converted, in situ, to 6,7,8,9-tetrahydrobenzo[4,5]thieno[2,3-d]-1,2,4-triazolo[4,5-a]pyrimidin-5-ones. The reaction mechanism was proposed and the products were screened for their biological activity. Some of the newly synthesized compounds had a moderate effect against some bacterial and fungal species.

The focal point of this research work is on the preparation of untreated and chemically treated abaca reinforced epoxy composites and the impact of these pre-treatments on tensile and flexural behavior of the composites. Alkali treatment, acrylation, permanganate treatment and benzenediazonium chloride treatments were carried out on abaca strands. Unprocessed and chemically processed fibers were used in the fabrication of epoxy composites with different fiber loadings of 20%, 30%, 40%, 50% and 60% using compression moulding technique. Tensile tests and flexural tests were performed using ASTM D638 [Type III] and ASTM D790 standards respectively. From these studies it can be concluded that chemical treatments are very effective in modifying the fiber surface, reducing the hydrophilic nature of fiber, improving fiber matrix adhesion there by increasing the mechanical performance of composites. Untreated Composites with 40% fiber loading and 10 mm fiber length showed maximum tensile strength of 36.48 MPa. For untreated as well as for all chemically treated abaca-epoxy composites, as the fiber loading surged from 10% to 40% , increment in tensile strength values were observed and beyond 40% it showed a decline. Benzenediazonium chloride treated fiber composites of 40% fiber loading showed maximum tensile strength of 58.62 MPa, followed by acrylic acid treatment, permanganate treatment and alkali treatment with tensile strength values of 50.28, 48.84, and 43.78 MPa respectively. Flexural strength also showed same trend as that of tensile strength. Benzenediazonium chloride treated fiber composites of 40% fiber loading showed maximum flexural strength of 67.86 MPa, followed by acrylic acid treatment, permanganate treatment and alkali treatment with flexural strength values of 60.24, 58.56, and 56.46 MPa respectively. Most of the studies were carried out for alkali treated composites but this study focused on acrylation, permanganate and benzenediazonium chloride treatments. These treatments enhanced tensile strength and flexural strength.

Reactions of N‐(5,5‐dimethyl‐3‐oxocyclohexenyl)‐S,S‐diphenylsulfilimine, a kind of enaminone, with isopentyl nitrite, isocyanates, isothocyanates, benzenediazonium chloride, and 1,1,1‐trifluoro‐4‐ethoxy‐3‐buten‐2‐one gave 1,2,5‐oxadiazole, isoxazole, isothiazole, 1,2,3‐triazole, and pyrrole derivatives condensed with cyclohexane, respectively, in one pot.

The reaction of 1,2-dihydro-6-(phenylamino)-2-thioxopyrimidin-4(3H)one (16) with N-arylhydrazonoyl halides 15 in CHCl3 in the presence of Et3N under reflux afforded the corresponding 1,2,4-triazolo[4,3-a]pyrimidin-5-ones of type 20 in good yields (Scheme 3). The structure of one of the derivatives, 20d, has been established by X-ray crystallography. Conceivable reaction mechanisms are discussed in Schemes 3 and 4. The products of type 20 easily undergo reactions with electrophiles such as benzenediazonium chloride, chloroacetyl chloride, and NaNO2 in AcOH to give 6-phenylazo, 6-chloroacetyl, and 6-nitroso derivatives 21, 23, and 25, respectively (Scheme 5).

New synthetic routes for triazolopyridine, pyridopyrimidine, pyridotriazine, imidazopyridine and pyri-dazine derivatives incorporating a coumarin moiety with interesting biological activities are reported. Reactions of the 2-oxo-4-(2-dimethylaminoethenyl)-2H-chromene-3-carbonitrile (4) and 2-amino-4-(2-dimethylaminoethenyl)quinoline-3-carbonitrile (5) with benzotriazol-1-yl-acetic acid hydrazide (6) affords the substituted [1,2,4]triazolo[1,5-a]pyrido[3,4-c]coumarines 9 and quinoline 12, respectively. Treatment of 4 with 2-amino-pyridine, glycine, urea, 3-aminocrotononitrile or cyanothioacetamide affords 14–18, respectively. Treatment of 3-amino-3,4-dihydro-4-imino-chromeno[3,4-c]pyridin-5-one (10) with α-chloro-acetylacetone affords pyridotriazine derivative 21. Compound 4 was also coupled with benzenediazonium chloride to afford 2-oxo-4-[2-oxo-1-(phenyl-hydrazono)-ethyl]-2H-chromene-3-carbonitrile 25. Treatment of the latter product with malononitrile afforded the 1-phenyl-3-(3′-Cyano-2′-oxo-coumarin-4′-yl)-6-oxo-pyridazine-5-carbonitrile (27). The structures of the newly synthesized compounds have been established on the basis of analytical and spectral data.

A mixture of both geometrical isomers of hydrazones 3a-3e was obtained by the coupling reactions of pyrazole-3-diazonium salts 2a-2d and benzenediazonium chloride 2e with 2-pyridylacetonitrile 1. Hydrazones 3a-3d were cyclized to the corresponding 4-amino-3-(2-pyridyl)pyrazolo[5,1-c][1,2,4]triazines 4a-4d.

2-Amino-3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophene with ethyl β-amino-α-cyano-γ-ethoxycarbonylcrotenoate yields the corresponding amide derivative. That compound reacts with benzenediazonium chloride to give the phenyl hydrazone derivative. This type of compounds was cyclized to give pyridazine and pyridine derivatives, respectively. Chemical reactivities of the latter were studied to give fused heterocyclic compounds with antimicrobial activities.

3-Dimethyl-1-[3-methyl-(4H)-5-phenylimidazol[2,1-b]thiazol-2-yl]prop-2-enone 4 couples smoothly with benzenediazonium chloride to yield propanal 5 which is a key intermediate for the synthesis of pyridazinones 9–13, 16 and pyridazine-6-imine 8, 19. Pentadienonitrile 18 was converted into pyridine-3-carbonitrile 20 on refluxing in ethanolic sodium ethoxide solution. Pyrazole 24 was synthesized from the reaction of 5 with 1-chloro-2-phenylhydrazono propan-2-one 22.

1,2-Dihydro-2-thioxopyrimidin-4(3H)ones 6 react with C-ethoxycarbonyl-N-arylhydrazonoyl chlorides 1 to give 1,2,4-triazolo[4,3-a]pyrimidines 11 in good yield. The latter products 11 react with benzenediazonium chloride, nitrous acid, acetyl chloride and chloroacetyl chloride to give the corresponding substitution products 16–18. The structures of the newly synthesized compounds are established on the basis of chemical and spectroscopic evidence.

Reaction of benzenediazonium chloride with active [1,2,4]triazin-3-ylthio-methylene compounds 3 afforded the azo coupling products 5, which yielded [1,2,4]triazolo[4,3-b][1,2,4]triazin-7(1H)-ones 8 upon treatment with sodium ethoxide in ethanol. The latter products 8 were characterized on the basis of alternate synthesis and spectral data. The mechanism of formation of 8 and the regiochemistry of the studied reactions are discussed.

Thiazole 1, when reacted with chloroacetyl chloride, afforded N-(5-acetyl-4-methylthiazol-2-yl) chloroacetamide 2. It has been found that compound 2 reacted with α-cyanocinnamonitrile derivatives 6a–c to afford reaction products 8a–c. Also, compound 2 coupled smoothly with benzenediazonium chloride afforded the phenylhydrazone 14. Coupling of the sulfonium bromide 17 with diazotized aromatic amines or N-nitrosoacetanilides afforded the arylhydrazones 20a,b. Treatment of 16 with 2-cyanoethanethioamide afforded [4-(2-amino-4-methylthiazol-5-yl) thiazol-2-yl] acetonitrile 22. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:362–369, 2000

WOS: A1996TT91100019 The C-13-NMR spectra of the azo dyes which were synthesized by reacting substituted benzenediazonium chloride with derivatives of some phenol have been measured. The spectral data of these compounds were described considering intramolecular hydrogen bond and not. The chemical shift assignments were made regarding substituent effects.

Uncross- and cross-linked polyoxetanes bearing o-, m-, and p-phenolic residual groups at the terminals of moderately long pendant spacers –CH2O(CH2)n–, where n=4 and 6, were prepared. The prepolymers having the pendant O-acetylated phenols were made by the BF3-initiated cationic ring-opening polymerization and then the pendant phenyl acetates were hydrolyzed with 2N aqueous NaOH in methanol to give the desired phenolic polyoxetanes. The pendant phenols were subjected to the diazocoupling reaction with 3 equiv of benzenediazonium chloride to examine their reactivities in aqueous media. Model polyoxetanes with the pendant phenyl benzoates containing the azo group were also prepared to confirm the structures of the diazocoupling product polymers.

The coupling of benzenediazonium chloride with benzoylacetone at two different pH values in 1:1 molar ratio gives two different tautomers, PHB and BAB, in that condensation of these dyes with isonicotinic acid hydrazide (INH) yields two different hydrazones PHBH and BABH. Thermal studies (DTA and TG) with spectral analyses (IR and electronic) have provided more information about the structure of PHBH which shows thermochromic behaviour. The d.c. electrical conductivities of these compounds were measured in the temperature range 25–70°C and were found to show semi-conducting behaviour. The activation energies for conduction were calculated. Valuable results were obtained from the comparison between Δ E of the azo and hydrazo tautomers, and of the dye and its hydrazone. A graphical method was suggested in order to make a simple comparison between the values of the electrical conductivity exponent.

Phenyltris((trifluoromethyl)sulfonyl)methane (CF 3 SO 2 ) 3 CC 6 H 5 , and its isomer ester (CF 3 SO 2 ) 2 =SCF 3 (O)-OC 6 H 5 are formed by the thermal decomposition of benzenediazonium tris((trifluoromethyl)sulfonyl)methanide, which was prepared by treatment of tris((trifluoromethyl)sulfonyl)methane, (CF 3 - SO 2 ) 3 CH, with benzenediazonium chloride.

3-Dimethyl-1-[3-methyl-(4H)-5-phenylimidazol[2,1-b]thiazol-2-yl]prop-2-enone 4 couples smoothly with benzenediazonium chloride to yield propanal 5 which is a key intermediate for the synthesis of pyridazinones 9–13, 16 and pyridazine-6-imine 8, 19. Pentadienonitrile 18 was converted into pyridine-3-carbonitrile 20 on refluxing in ethanolic sodium ethoxide solution. Pyrazole 24 was synthesized from the reaction of 5 with 1-chloro-2-phenylhydrazono propan-2-one 22.

A relational database manager (DB) was previously employed to estimate values of kinetic parameters from isothermal TG (ITG) and from non-isothermal TG (NITG) data. The Paradox 3 DB, which possesses a powerful application language ( pal ), was utilized to estimate values of reaction order n and activation energy E , and to ascertain the most probable decomposition mechanism from among 10 possibilities. When these results were compared with reported values, they were found to be in satisfactory agreement. The aim of this paper is to extend the utilization of pal in the determination of values of E and n from NITG data. A cubic expression was employed which involves the use of slopes from TG curves at particular values of α. Analyses were carried out using theoretical TG data, benzenediazonium chloride, and magnesium hydroxide.

A powerful relational database manager (DB), Paradox 3.0, was previously applied satisfactorily by the author to ascertain values of reaction order ( n ) and rate constant ( k ) from isothermal TG (ITG) data. This DB possessed an extensive Paradox Application Language (PAL) which could be utilized to write scripts pertaining to the determination of kinetic parameters from TG data. The aim of this paper is to extend the application of DBs such as Paradox 3.0 to thermal analysis. Thus, PAL was employed to write a script (just as macros in spreadsheets were previously written and used in thermal analysis by the author) to determine values of n and activation energy ( E ) from non-isothermal TG (NITG) data. In this regard, a PAL script was written and applied to theoretical NITG data as well as to NITG data for calcium oxalate monohydrate, calcium carbonate, teflon and benzenediazonium chloride.

Recently, spreadsheet procedures were successfully utilized by the present author to ascertain the activation energy E and reaction order n, or E and the mechanism, from TG or DTA data. In this paper, such procedures are applied, using another algorithm, to theoretical TG data, to TG data for magnesium hydroxide (MH) and finally to DTA data for benzenediazonium chloride in aqueous solution (BDC). The aim of this paper is to popularize and extend the implementation of spreadsheets in thermal analysis.

A novel one-pot synthesis of 3-bromomethylbenzo [d] isoxazole (3) utilizing o-hydroxy-α-bromoacetophenone is reported. Coupling of 3 with benzenediazonium chloride afforded, the first reported, C-(3-benzo [d] isoxazolyl)-N-(phenyl) formohydrazidoyl bromide (13). The chemical behaviour of 3 and 13 towards a variety of chemical reagents has been investigated

4,5-Diphenyl-2-mercaptoimidazole (I) was reacted with hydrazidoyl halides IIa−d to give the S-alkyl derivatives IIIa−d. Cyclization of IIIa−d afforded imidazo[2, 1−b]-thiazole derivatives VIa,b and VII. Treatment of I with α-chloroethylacetoacetate (IV) gave ethyl 2-(4,5-diphenyl-2-imidazolinylthio)-3-keto-butyrate (V). Compound V coupled with benzenediazonium chloride to give the corresponding phenylhydrazo compound IIId. On heating V with polyphosphoric acid, cyclization took place and 2-acetyl-5,6-diphenyl-imidazo[2, 1−b]thiazol-3-one (VIII) was obtained. The compound VIII was condensed with aromatic aldehydes to yield the cinnamoyl derivatives IXa,b. The antimicrobial activities of compounds IIIa−d, V, VIa, VII were examined.

5-arylidene-2-thiohydantoins 1a–c react with ethyl α -chloroacetate 2 and monochloroacetone to give the respective 2-imidazolinones 3a–c and 2-acetonylmercaptohydantoins 9a–c . Compounds 3a–c react with benzenediazonium chloride to afford hydrazones 5a–c . The reaction of 1a–c with ethylene bromide and with α,α -dichloroacetone gives the respective alkyl mercapto-derivatives 13a–c and 14a–c . The reaction of polyphosphoric acid with 3a–c , 9a–c , 13a–c and 14a–c yields the respective thiazolones 7a–c , imidazothioles 10a–c , imidazo-thiazoles 15a–c and imidazothiazines 16a–c . The mercapto-hydantoins 17a–d react with anthranilic acid to give quinazolin-3,5-diones 19a,b and/or 21a , b . Structural elucidation for the new products are based on compatible elementary and spectroscopic evidences.

[100-56-1] C6H5ClHg (MW 313.15) InChI = 1S/C6H5.ClH.Hg/c1-2-4-6-5-3-1;;/h1-5H;1H;/q;;+1/p-1 InChIKey = AWGTVRDHKJQFAX-UHFFFAOYSA-M (phenylating agent for allylic halides3 and alkenes;4-8 converts primary and secondary allylic alcohols into 3-phenyl alcohols and 3-phenyl aldehydes;9 reacts with carbon monoxide to give ketone10-13) Physical Data: mp 250–252 °C. 1H NMR:16, 17 δ (DMSO, ppm) Ho 7.46 (3JHo–Hg = +203 Hz); Hm 7.37 (4JHm–Hg = +49 Hz); Hp 7.46. 13C NMR:18, 19 δ (DMF + (CD3)2CO (20%) at 340 K (ppm)) Cα 150.5, (1JHg–C = 2530 Hz), Cβ 136.4 (2JHg–C = 117 Hz); Cγ 128.0 (3JHg–C = 205 Hz); Cδ 127.9 (4JHg–C = 35 Hz). 199Hg NMR:18 (CH2Cl2) −1192, ((CD3)2SO) −1182 ppm. MS:20 mass of ions observed: C6H5HgCl+, C6H5Hg+, HgCl+. IR: ν(Hg–Cl) 331–332 cm−1.15 Solubility: sparingly sol H2O; sol C6H6, ether, pyridine; slightly sol hot ethanol.2 Form Supplied in: white satiny leaflets; stable in air; widely available. Preparative Method: by mercuration of benzene21 with Mercury(II) Chloride (eq 1) or red Mercury(II) Oxide. (1) Copper or Copper(I) Chloride22 promotes facile displacement of nitrogen from double salts of Benzenediazonium Chloride and mercury(II) chloride in good yield (eq 2). (2) Phenylmercury(II) chloride can also be prepared by the Peters reaction23 involving mercury(II) chloride and sulfinic acid (eq 3), by the decomposition of the phenyl–tin bond in PhSn(alkyl)3 with mercury(II) chloride (eq 4),24 by mixing equimolar mercury(II) chloride and Diphenylmercury (eq 5),25 or by photolysis of diphenylmercury in CCl4 (eq 6).26 (3) (4) (5) (6) In PhHgCl the PhHg bond is less polar than the HgCl bond. The PhHg bond is weak and undergoes homolytic cleavage. Handling, Storage, and Precautions: highly toxic irritant; LD50 orally in rats 60 mg kg−1. Use in a fume hood.

Reaction of benzenediazonium chloride with active [1,2,4]triazin-3-ylthio-methylene compounds 3 afforded the azo coupling products 5, which yielded [1,2,4]triazolo[4,3-b][1,2,4]triazin-7(1H)-ones 8 upon treatment with sodium ethoxide in ethanol. The latter products 8 were characterized on the basis of alternate synthesis and spectral data. The mechanism of formation of 8 and the regiochemistry of the studied reactions are discussed.

Thiazole 1, when reacted with chloroacetyl chloride, afforded N-(5-acetyl-4-methylthiazol-2-yl) chloroacetamide 2. It has been found that compound 2 reacted with α-cyanocinnamonitrile derivatives 6a–c to afford reaction products 8a–c. Also, compound 2 coupled smoothly with benzenediazonium chloride afforded the phenylhydrazone 14. Coupling of the sulfonium bromide 17 with diazotized aromatic amines or N-nitrosoacetanilides afforded the arylhydrazones 20a,b. Treatment of 16 with 2-cyanoethanethioamide afforded [4-(2-amino-4-methylthiazol-5-yl) thiazol-2-yl] acetonitrile 22. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:362–369, 2000

A novel one-pot synthesis of 3-bromomethylbenzo [d] isoxazole (3) utilizing o-hydroxy-α-bromoacetophenone is reported. Coupling of 3 with benzenediazonium chloride afforded, the first reported, C-(3-benzo [d] isoxazolyl)-N-(phenyl) formohydrazidoyl bromide (13). The chemical behaviour of 3 and 13 towards a variety of chemical reagents has been investigated

Reaction of benzenediazonium chloride with 3,4-diphenyl-1,2,4-triazol-5-ylthiomethylene compounds 3 afforded the azo coupling products 4, which upon treatment with sodium ethoxide in ethanol yielded the title compounds that rearrange in situ to give the thiohydrazides 7.

In the decomposition of benzenediazonium chloride (BDC) in the presence of peracetic acid, o-chlorophenol (OCP) was obtained. When the molar ratio of peracetic acid against BDC was less than unity, only OCP was obtained. The sum of the yields of parachlorinated products such as p-chlorophenol, 2, 4-dichlorophenol (2, 4-DCP) and 2, 4, 6-trichlorophenol (TCP), incresed with the molar ratio. p-Toluenediazonium chloride (TDC) also showed the same tendency. It should be noted that in no case was 2-chloro-p-cresol (OCPC) formed without peracetic acid, but p-cresol (PC), p-chlorotoluene (PCT) and p-tolyl acetate (PTA) were formed. No toluene or p, p'-bitolyl could be detected.The rate constant for the consumption reaction of peracetic acid in the titled decomposition reaction of BDC was equal to that in the reaction with phenol instead of BDC, and smaller than that of the decomposition of BDC. This should be the rate constant for the formation of chlorinating species, considered to be acetyl hypochlorite, judging from the o/p ratio of chlorophenol formed. In the reaction of TDC, the rate constant for the consumption of peracetic acid was greater than the decomposition rate constant of TDC equal to that for the formation of any product.From these findings, a probable mechanism involving an attack of acetyl hypochlorite formed by the oxidation of chloride anion with peracetic acid on phenols produced by the ionic decomposition of benzenediazonium chlorides is postulated and discussed.

1-Phenyl-4-thiohydantoin reacted with aryldiazonium salts to give the corresponding 5-arylazo-1-phenyl-4-thiohydantoin (1 a-f). On alkylation of 1 a, b,f with different alkyl halides, the corresponding 4-alkylmercapto derivatives (2a-f) were obtained. 2 a was hydrolysed with a mixture of ethanol-hydrochloric acid to give 5-phenylazo-1-phenyl-hydantoin (3). Treatment of 2 a, d with amines gave the products 4a—h. 4 a when refluxed with a mixture of acetic-hydrochloric acid, the product 3 was obtained, 1a, b reacted with formaldehyde and appropriate amine to give the corresponding Mannich bases 5 a-k. Also 1-phenyl-4-thiohydantoin when exposed to the Mannich reaction, 6a-e were obtained, 6 a when treated with benzenediazonium chloride, the colour substance 5 a was separated.

The 1 H-, 13 C- and 15 N-NMR spectra of compounds prepared by coupling benzenediazonium chloride with J-acid, H-acid and Gamma acid under alkaline conditions have been measured. Two-dimensional H,H-COSY, NOESY, H,C-COSY and COLOC spectra and one-dimensional selective INEPT have been used in the assignment of the 1 H- and 13 C-NMR signals. The results show that the above-mentioned aminohydroxynaphthalene-sulfonic acids undergo diazo coupling of benzenediazonium chloride ortho to the hydroxyl groups under alkaline conditions. Using δ( 13 C), δ( 15 N) and 1 J( 15 NH) it has been found that the coupling products exist, in hexadeuteriodimethyl sulfoxide solutions, as equilibrium mixtures of the azo and hydrazone tautomers with strongly prevailing naphthoquinone phenyl-hydrazone configurations.

13C NMR spectra of four types of azo coupling products from benzenediazonium chloride have been measured and interpreted, viz. hydrazo compounds with an intramolecular hydrogen bond (3-methyl-1-phenylpyrazole-4,5-dione 4-phenylhydrazone), azo compounds without an intramolecular hydrogen bond (4-hydroxyazobenzene), azo compounds with an intramolecular hydrogen bond (2-hydroxy-5-tert-butylazobenzene) and an equilibrium mixture of both the tautomers of 1-phenylazo-2-naphthol. The absolute values of the J(15N13C) coupling constants have been determined by recording the spectra of the 15N isotopomers, and have been used, in some cases, for 13C signal assignment. A relationship has been found between the chemical shifts of the C-1′ to C-4′ carbons of the phenyl group (from the benzenediazonium ion) or the 1J(15N13C) coupling constant, and the composition of the tautomeric mixture.

Chlorination of the title compound gave 5′- and 3′-chloro-2′-hydroxy-4′,6′-dimethoxyacetophenone. The nitration of its acetate, followed successively by reduction, diazotization, and reaction with cuprous chloride, gave the 3′-substituted series, 2′-acetoxy-4′,6′-dimethoxy-3′-nitroacetophenone, 3′-amino-2′-hydroxy-4′,6′-dimethoxyacetophenone, and 3′-chloro-2′-hydroxy-4′,6′-methoxyacetophenone, respectively. The orientation of substituents in the products was proved. The amino and chloro members of the isomeric 5′-substituted series were availablevia 2′-hydroxy-4′,6′-dimethoxy-5′-phenylazoacetophenone, the product of the reaction of the title compound with benzenediazonium chloride.

Whereas phenyl radicals from dibenzoyl peroxide or phenylazotriphenylmethane abstract bromine almost exclusively, rather than chlorine, from bromotrichloromethane, decomposition at 50 °C of N-nitrosoacetanilide (NNA), also an established source of phenyl radicals, leads to both bromo- and chloro-benzene thus providing a further example of ‘anomalous’ halogen abstraction involving NNA and polyhalogenomethanes. Reaction at 20 °C leads to the precipitation of a mixture of benzenediazonium chloride and acetate, the bromide being absent, and to the formation of bromobenzene and little chlorobenzene. Heating this mixture of diazonium salts at 50 °C in bromotrichloromethane leads to mainly chlorobenzene and some phenyl acetate. Also formed in the reaction of NNA with bromotrichloromethane are significant amounts of carbon dioxide (23 mol per 100 mol NNA), acetic anhydride (14.5), and acetic acid (62). Reaction in the presence of the radical trap, 1,1-diphenylethene (1 mol. equiv.), leads to suppression of chlorobenzene, i.e. the reaction is restored to normality. Isolation of 9-phenylphenanthrene is evidence of competing formation of benzyne in this reaction. These results point to the occurrence of abstraction of bromine by phenyl radicals from bromotrichloromethane to give trichloromethyl, which is scavenged by phenyldiazo-oxyl (1) to give trichloromethylbenzenediazoate (2); this in turn gives the observed benzenediazonium chloride, and hence chlorobenzene, and phosgene. Reaction of phosgene with NNA leads to more diazonium chloride, carbon dioxide, and acetic anhydride. In support of this, silver benzenediazoate reacts with bromotrichloromethane to give benzenediazonium chloride. The reaction in the presence of 1,1-diphenylethene leads to an increase in yield of bromobenzene thus pointing to decomposition of phenyldiazo-oxyl, in this case, via electron transfer with the radical Ph2Ċ·CH2·CCl3, to give a phenyl radical. p-Nitro-N-nitrosoacetanilide also reacts with bromotrichloromethane via dual or ‘anomalous’ abstraction of halogen, superimposed on scrambling of aromatic substituents via nucleophilic displacement by chloride and acetate of the activated p-nitro-group in the p-nitrobenzenediazonium ion.Attention is drawn to the relevance of these results to other anomalous halogen abstraction reactions of NNA in chloroform and in carbon tetrachloride.

Spreadsheets have rarely been used to analyze TG and DTA (or DSC) data to obtain activation energy E and reaction order n (or mechanism). In the recent past and in this paper spreadsheet procedures have been successfully used to ascertain E and n or E and mechanism. In this paper, these procedures are applied to theoretical TG data, to TG data for calcium oxalate, calcium carbonate, teflon and sodium bicarbonate and to DTA data for benzenediazonium chloride. In addition, some of the many advantages of using such procedures are mentioned. The aim of this paper is to extend the implementation of spreadsheets in thermal analysis.