Reaction Of Diazonium Salts Research Articles

Chemistry of Hydrazonoalkanenitriles

- Reactions of arene and heteroaromatics diazonium salts with active methylene compounds having cyano group have been illustrated to afford hydrazonoalkanenitriles with a range of substituents. Structural investigation for hydrazonoalkanenitriles has been made. Furthermore the reactivity of hyrazonoalkanenitriles towards nucleophilic and electrophilic reagents has been displayed.

X-Ray crystal structure determination of a series of 1-aryl- 2-[3-(3-[2-aryl-1-diazenyl]-1,3-diazepan-1-ylmethyl)-1, 3-diazepan-1-yl]-1-diazenes obtained from the reaction of diazonium salts with mixtures of formaldehyde and 1,4-diaminobutane

A new series of bis-triazenes, the 1-aryl-2-[3-(3-[2-aryl-1-diazenyl]-1,3-diazepan-1-ylmethyl)-1,3-diazepan-1-yl]-1-diazenes has been synthesized from the reaction of diazonium salts with a mixture of 1,4-diaminobutane and formaldehyde. The structures of 1-(p-bromophenyl)-2-[3-{3-[2-(p-bromophenyl)-1-diazenyl]-1,3-diazepan-1-ylmethyl}-1,3-diazepan-1-yl]-1-diazene(1), 1-(p-cyanophenyl)-2-[3-{3-[2-(p-cyanophenyl)-1-diazenyl]-1,3-di azepan-1-ylmethyl}-1,3-diazepan-1-yl]-1-diazene(2), and 1-(p-methoxyphenyl)-2-[3-{3-[2-(p-methoxy-phenyl)-1-diazenyl]-1,3-diazepan-1-ylmethyl}-1,3-diazepan-1-yl]-1 diazene(3) have been unequivocally determined by X-ray crystallography. The new bis-triazenes are important since the structure contains the novel saturated heterocycle, 1,3-diazepane. The general conclusion of this study is that alkanediamines with 3 or 4 carbon atoms in the spacer link between the nitrogen atoms give rise to the linear bicyclic molecules of type 5, in contrast to the case of ethylenediamine (spacer link 2 carbon atoms), which affords molecules of type 6, which exemplify the general cage structure of type 4. The crystal structures of 1, 2 and 3 are compared with the previously reported structure of the hexahydropyrimidine analogue 8a(X=CN); compounds 2 and 8a(X=CN) are homologous with respect to the alkane spacer moiety. The structures of 2 and 8a(X=CN) are very different in one respect; in 2 the aryldiazenyl-1,3-diazepanyl groups are in the s-trans orientation around the central methylene group whereas in 8a(X=CN) the arrangement of the aryldiazenyl-hexahydropyrimidinyl groups is the s-cis orientation. Crystal data: 1 C23H30N8Br2, triclinic, space group P-1, a=8.3979(2), b=10.7828(3), c=14.4692(5) A, α=83.670(1), β=78.662(1), γ=78.758(1)°, V=1256.48(6) A3, for Z=2. 2 C25H30N10, monoclinic, space group P2 1 /n, a=13.4046(6), b=9.4482(4), c=10.6913(4)A, β=103.239(2)°, V=2490.5(2) A3, for Z=4. 3 C25H36N8O2, triclinic, space group P-1, a=8.5223(3), b=10.6913(4), c=14.4034(7)A, α=85.657(2), β=78.731(2), γ=80.153(1)°, V=1266.88(9) A3, for Z=2.

Triazene derivatives of (1,x)-diazacycloalkanes. Part VII. Synthesis of a series of 1-aryl-2-[3-(3-[2-aryl-1-diazenyl]-1,3-diazepan-1-ylmethyl)-1,3-diazepan-1-yl]-1-diazenes from the reaction of diazonium salts with mixtures of formaldehyde and 1,4-diaminobutane

A new series of bistriazenes, the 1-aryl-2-[3-(3-[2-aryl-1-diazenyl]-1,3-diazepan-1-ylmethyl)-1,3-diazepan-1-yl]-1-diazenes (8), has been synthesized from the reaction of diazonium salts with a mixture of 1,4-diaminobutane and formaldehyde. All new compounds of series 8 have been characterized by IR and NMR spectroscopy, and the elemental composition of selected examples has been verified by elemental analysis. The connectivity of the series has been unequivocally determined by X-ray crystallography. The new bistriazenes are important because the structure contains the novel saturated heterocycle, 1,3-diazepane. The general conclusion of this study is that alkanediamines with three or four carbon atoms in the spacer link between the nitrogen atoms give rise to the linear bicyclic molecules of type 2, in contrast to the case of ethylenediamine (two carbon atoms in spacer link), which affords molecules of type 3, which exemplify the cage structure of type 1.Key words: diazonium salt, triazene, bistriazene, diazepane, formaldehyde, nuclear magnetic resonance.

Synthesis and characterization of new azobenzenesulfonic acids doped conducting polyaniline

New azobenzene sulfonic acid dopants were synthesized by diazotized coupling reaction of sulphanilic acid diazonium salt with commercially available raw materials such as phenol, m-cresol and 4-phenylphenol. The structures of the dopants are confirmed by NMR and FT-IR. Polyaniline emeraldine base was doped by these new azobenzenesulfonic acid dopants in two different solvent medium such as methanol and N-methylpyrrolidinone to produce green emeraldine salt. The doping process was confirmed by FT-IR and UV–vis spectroscopy. The effect of composition of dopant on the conductivity of the polyaniline was investigated and the results suggest that the conductivity increases with the increase in the dopant concentration and attained maxima for more than 38% in the feed. The conductivity measurements reveal that all the dopants equally effective in producing in high conductivity in the range of 0.02 S/cm and the conductivity of the doped samples are insignificant to the structural difference in the dopant. WXRD and SEM analysis indicate that the doped samples are highly amorphous and porous in nature. The thermal analysis by TGA indicate that all the doped materials were highly stable up to 300 °C for high temperature applications.

A Series of 1‐[2‐Aryl‐1‐diazenyl]‐3‐({3‐[2‐aryl‐1‐diazenyl]perhydrobenzo [d]imidazol‐1‐yl}methyl)perhydrobenzo[d]imidazoles. Synthesis and Characterization.

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Synthesis of cesium selective pyridyl azocalix[ n]arenes

A series of pyridylazo calix[ n]arenes ( n=4, 6, 8) including the first examples of mixed hetroaryl azocalix( n)arenes have been synthesized by coupling calix[ n]arenes with diazonium salts derived from amino pyridines. It has been observed that the coupling reaction of diazonium salt obtained from 3-aminopyridine with calix[ n]arene gives tetrakis-, hexakis- and octakis (pyridylazo)calix[ n]arenes ( n=4,6,8) while those derived from 4-aminopyridine give partially substituted (4-pyridylazo)calix[ n]arene analogs. There is no reaction of calix( n)arenes with diazonium salts derived from 2-aminopyridine under identical conditions of experiments. The conformational analysis of synthesized compounds have been ascertained by detailed spectral measurements and single crystal X-ray analysis of 5-(3′-pyridylazo)-25,26,27,28-tetrahydroxycalix[4]arene. A rational explanation for the observed partial and exhaustive coupling reaction in the synthesis of heteroaryl azocalix( n)arenes has been suggested. Preliminary evaluation of synthesized derivatives as molecular receptors for metal ions indicates that they have good potential to function as selective ionic filters for cesium ions.

Triazene derivatives of (1,x)-diazacycloalkanes. Part V.1 Synthesis and characterization of 4-ethyl-3-({6-ethyl-3-[2-aryl-1-diazenyl]hexahydro-1-pyrimidinyl}methyl)-1-[2-aryl-1-diazenyl)hexa- hydropyrimidines from the reaction of diazonium salts with mixtures of formaldehyde and 1,3-diaminopentane

A new series of bistriazenes has been synthesized from a general reaction of diazonium salts with a mixture of 1,3-diaminopentane (DYTEK® EP diamine) and formaldehyde, which affords the 4-ethyl-3-({6-ethyl-3-[2-aryl-1-diazenyl]hexahydro-1-pyrimidinyl}methyl)-1-[2-aryl-1-diazenyl]hexahydropyrimidines (1). Each of the molecules of type 1 is built up of two equivalent 3-(aryldiazenyl)-6-ethylhexahydro-1-pyrimidinyl groups attached to a central methylene group. The importance of this study is in part due to the fact that the formaldehyde–1,3-diaminopentane system has not previously been investigated. All new compounds have been characterized by IR and NMR spectroscopy, with elemental analysis for selected compounds; one example from the series has been unequivocally characterized by X-ray crystallography. Although analysis of the NMR spectra is made somewhat difficult because of broadness and coalescence of signals due to the rotational dynamics of the N—N single bonds, it is possible to fully assign the proton spectra of all compounds and to detect 94% of all carbon signals. The fine structure within the proton spectra illustrate the diastereotopic nature of the methylene group protons because of the presence of a stereocenter in each hexahydropyrimidine ring. The general conclusion of this study is that alkanediamines with three carbon atoms in the spacer link between the nitrogen atoms give rise to the linear bicyclic molecules of type 1, 2, and 3, in contrast to the case of ethylenediamine (spacer link has two carbon atoms), which affords molecules of type 7 that exemplify the bridged bicyclic bistriazene structure. The new compounds of series 1 represent an extension of a broad ranging study of the synthesis of new bistriazene derivatives of (1,x)-diazacycloalkanes.Key words: triazene, diazonium coupling, hexahydropyrimidine, diaminopentane, diazacycloalkanes, stereocenter, diastereotopic protons.

Triazene derivatives of (1,x)-diazacycloalkanes. Part IV.1 Synthesis and characterization of 1-[2-aryl-1-diazenyl]-3-(3-[2-aryl-1-diazenyl]hexahydro-1-pyrimidinylmethyl)hexahydropyrimidines and 1-(5,5-dimethyl-3-[2-aryl-1-diazenyl]hexahydro-1-pyrimidinylmethyl)-5,5-dimethyl-3-[2-aryl-1-diazenyl]hexahydropyrimidines from the reaction of diazonium salts with mixtures of formaldehyde and 1,3-diaminopropanes

Two new series of bistriazenes have been synthesized from a general reaction of diazonium salts with a mixture of a propanediamine and formaldehyde. Such reaction with 1,3-diaminopropane itself affords the 1-[2-aryl-1-diazenyl]-3-(3-[2-aryl-1-diazenyl]hexahydro-1-pyrimidinylmethyl)hexahydropyrimidines (6). 2,2-Dimethyl-1,3-diamino propane reacts in an analogous manner to give the 1-(5,5-dimethyl-3-[2-aryl-1-diazenyl]hexahydro-1-pyrimidinylmethyl)- 5,5-dimethyl-3-[2-aryl-1-diazenyl]hexahydropyrimidines (7). All new compounds have been characterized by IR and NMR spectroscopy, with elemental analysis or high resolution mass spectrometry of most of the new compounds. NMR assignments have been analyzed by a series of DEPT, COSY, and HSQC experiments. One example of each series has been unequivocally characterized by X-ray crystallography. The general conclusion of this study is that alkanediamines with three carbon atoms in the spacer link between the nitrogen atoms give rise to the linear bicyclic molecules of type 18, in contrast to the case of ethylenediamine (spacer link has two carbon atoms), which affords cage-like molecules of type 17.Key words: bistriazene, hexahydropyrimidine, diazonium coupling, formaldehyde, diaminopropane, nuclear magnetic resonance.

Otrzymywanie i wlasciwosci fotoczulych, organicznych i hybrydowych (nieorganiczno-organicznych) materialow polimerowych z chromoforowym ugrupowaniem diazenylowym

Two methods of the synthesis of new photosensitive methacrylate polymers (PM) or hybrid polymer materials (PH) containing chromophoric diazene moieties of structures described by general Formulas (I), (II) or (III) were presented. The first one (Scheme A) was based on radical polymerization of chromophoric methacrylate monomer (MM) or copolymerization of this monomer with a non-chromophoric MM in solution. An alternative way to get the title polymers was modification of non-chromophoric polymers by coupling reaction of diazonium salts with dialkylaminophenyl group present in the side chain of the polymers (Scheme B). The yield of the synthesis of chromophoric PM was above 70 %, their number average molecular weight was in the range 3400-23000 and polydispersity was 1.1-3.0. All PM obtained (homo-, co- and terpolymers) were able to form transparent photosensitive films on glass substrates. The photosensitive PH materials (XV) were obtained via sol-gel process. The first step of the process was reaction of the free OH groups containing monomers (IV) (Scheme A) or co- and terpolymes PH [(X), R5 or R6 = CH2CH2OH; Scheme A] with 3-(triethoxysilyl)propyl isocyanate (ICTESP) followed by co-hydrolysis and condensation reaction of the resulting carbamate with tetraethoxysilane. The sol obtained was deposited onto glass plates and hardened to transparent glassy film at ca. 120 oC. The chromophoric methacrylate polymers showed reverse trans-cis isomerization [reaction (5); Fig. 1] in solutions and in thin films under illumination with light. The course of isomerization was dependent on the kind of material containing the chromophore moiety and reaction environment (solution, film). The organic and hybrid polymer glass showed ability to form holographic grating on the films in two beam coupling arrangement with using green laser (532 nm) use. The grating formation was reversible at relatively short illumination period but relatively stable when prolonged beam interference caused thickness gradient in the film. Both types of the gratings could be used in holographic data recording. Detail characteristics of PM and PH obtained (chemicals structure, yield of synthesis, values of Mn, Mw/Mn, Tg as well as parameters describing trans"cis isomerization) are given in Table 1.

Mixed Anionoarylation of Tetramethylene and Diethylene Glycol Diacrylates

The example of tetramethylene and diethylene glycol diacrylates was used to accomplish the first mixed anionoarylation. The reaction of diazonium salts with these unsaturated compounds gave chloroarylation adducts by one multiple bond: 1-acryloyloxy-4-(2-chloro-3-arylpropyonyloxy)butanes and 1-acryl-oyloxy-2-[2-(2-chloro-3-arylpropyonyloxy)ethoxy]ethanes. The latter were subjected to thiocyanatoarylation to obtain diadducts: 1-(2-chloro-3-arylpropyonyloxy)-4-(2-thiocyanato-3-arylpropyonyloxy)butanes and 1-(2-chloro-3-arylpropyonyloxy)-2-[2-(2-thiocyanato-3-arylpropyonyloxy)ethoxy]ethanes.

Catalytic Sandmeyer Cyanation as a Synthetic Pathway to Aryl Nitriles.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Catalytic Sandmeyer cyanation as a synthetic pathway to aryl nitriles

Aryl nitriles ArCN were obtained by the Cu(I)/Cu(II) catalysed reaction of aryl diazonium salts with KCN in good yields.

Probing the mechanism of the Heck reaction with arene diazonium salts by electrospray mass and tandem mass spectrometry.

Key ionic intermediates of the Heck reaction of arene diazonium salts have been intercepted and structurally characterized by ESI-MS/MS. The use of electrospray ionization enables the ionic species to be transferred smoothly to the gas phase. A catalytic cycle for this reaction involving all the Pd cationic species intercepted has been proposed (see scheme).

Synthesis of styrylcoumarins from coumarin diazonium salts and studies on their spectra characteristics

A facile synthesis of styrylcoumarins based on Palladium-catalyzed reaction of coumarin diazonium salts with substituted styrenes is described. The reactions produced a series of 7-styrylcoumarins in good yields under mild conditions. The absorption and emission spectra of different styrylcoumarins were compared and discussed. Although the λ a,max of the styrylcoumarins changed only slightly with a p-substituted styrene, the λ e,max produced a blue shift which increased with the electron-withdrawing ability of the p-substituted group. The p-CH 3 of styrylcoumarin caused a red shift of ca. 20 nm and also a higher fluorescence quantum yield. Styrylcoumarins with o, p-CN obtained well-resolved vibrational bands and the latter possessed higher fluorescence quantum yield. In addition, a coumarin extended at both the 3-positions with benzene and 7-position with p-chlorostyrene had better fluorescence properties.

ChemInform Abstract: Reactions of Diazonium Salts with Phenyl Dithiocarbamate. Part 2. Formation of Related Arylazophenyldithiocarbamates.

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M-Aminophenylarsonic Acid as an Analytical Form for the Photometric Determination of Phenol in Water

The azocoupling reaction of diazonium salts of o- and m-aminophenylarsonic acids with phenol was studied. On the basis of quantum-chemical calculations of the reagents, conformation analysis of resulting azo compounds, and experimental data, it was found that the meta isomer of aminophenylarsonic acid is of practical interest as an analytical reagent for the determination of phenol. The advantage of the proposed reagent is a high stability of the diazonium salt. A procedure was developed for the spectrophotometric determination of phenol in water at a level of 0.06 μg/mL. The error in the determination is no higher than 5.5%.

Reactions of diazonium salts with phenyl dithiocarbamate. Part-II. Formation of related arylazophenyldithiocarbamates

Reactions of diazonium salts with phenyl dithiocarbamate. Part-II. Formation of related arylazophenyldithiocarbamates

15N,13C and1H NMR study of azo coupling products from diazonium salts and enaminones

Reactions of diazonium salts with 4-substituted phenylaminopent-3-en-2-ones produce the corresponding 4-phenylimino-3-phenylhydrazonopentan-2-ones. On the other hand, the reaction of diazonium salt with 4-amino(or 4-methylamino)pent-3-en-2-one gives a mixture of two isomers approaching the tautomeric form of 4-amino-3-phenylazopent-3-en-2-ones. The tautomeric form of the individual coupling products was determined by means of 13C and 15N NMR chemical shifts and J(15N,H) coupling constants. With the help of TPPI-NOESY spectra it was possible to follow the rate of mutual exchange of four protons of NH groups in both isomers of 4-amino-3-(4-methylphenylazo)pent-3-en-2-one. Copyright © 2000 John Wiley & Sons, Ltd.

High and low molar mass 3‐alkyl‐1,4‐pentazadienes. Synthesis and photolysis

AbstractHigh and low molar mass compounds containing the 3‐alkyl‐1,4‐diarylpentazadiene group were synthesized in the reaction of aromatic diazonium salts with primary amines. These high nitrogen compounds are characterised by high photosensitivity and thermostability. The photolytic decomposition was studied in detail with respect to the substitution at the aromatic moieties and at N3 of the pentazadiene chromophore. Electron donating aromatic substituents were found to increase photosensitivity and decrease thermostability whereas electron withdrawing aromatic substituents cause higher photolytic and thermolytic stability. A little influence of the alkyl group at N3 on the photosensitivity of the pentazadiene group was observed. Photolysis was investigated by means of UV/Vis spectroscopy and obeys first order kinetics for some compounds under investigation. Gel permeation chromatography (GPC) measurements during photolysis of pentazadiene polymers prove that irradiation with UV light causes irreversible chain degradation. Thermolysis in bulk was studied for all compounds by differential scanning calorimetry (DSC). In contrast to the results of the photolysis the alkyl substituent at N3 has an effect on the thermostability of the pentazadiene chromophore.

ChemInform Abstract: Preparation and Reactions of Diazonium Salts. Part 2. Reactions of ArN+ 2

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.