Convenient Preparation of N,N′‐Diphenyl‐N,N′‐bis(4‐aminophenyl)‐p‐phenylenediamine

Abstract

This article describes modified conditions to prepare N,N′‐diphenyl‐N,N′‐bis(4‐aminophenyl)‐P‐phenylenediamine in 60% overall yield.     

Convenient Synthesis of N,N′‐bis‐protected‐3,3′‐diiodo‐2,2′‐biindoles

A convenient synthesis of N,N′‐bis‐protected 3,3′‐diiodo‐2,2′‐biindoles 4–7 from 2,2′‐biindole (1) is described.     

Synthesis of New 1,3‐bis(Heteroaryl)‐4,5‐imidazolidinediones Through Reaction of N,N′‐bis(Heteroaryl)methanediamines with Oxalyl Chloride

Reaction of N,N′‐bis(2‐pyridinyl, 3‐pyridinyl, 4‐pyridinyl, 2‐thiazolyl, 4‐nitrophenyl, and 2‐benzothiazolyl)methanediamines 1a–f with oxalyl chloride in dry dichloroethane in the presence of pyridine affords the corresponding 1,3‐bis (heteroaryl)‐4,5‐imidazolidinediones 3a–f in good to excellent yields. The essential role of pyridine in the reaction mixture is described, and reaction details as well as product characterization is discussed.     

Nanoporous Crosslinked Copolymers Prepared by Thermal Degradation of Poly(Methacryl‐N,N′‐diisopropylurea‐co‐ethylene Glycol Dimethacrylate)

Abstract

Copolymers of methacryl‐N,N′‐diisopropylurea (MA‐DiPrU) with ethylene glycol dimethacrylate (EDMA) at monomer‐to‐monomer ratios in the feed: 0.3/0.7; 0.5/0.5; 0.7/0.3; 0.8/0.2 were prepared in butanone in the presence of 2% of dibenzoyl peroxide (Bz₂O₂) at 70°C for 48?hr. Copolymers regardless of the ratio of comonomers in the feed decompose thermally at 200–250°C under the separation of isopropylisocyanate (iPrNCO). Residues after the removal of iPrNCO are thermally stable nanoporous crosslinked copolymers of methacryl‐isopropylamide (MA‐iPrA) with EDMA which decompose by a one‐step mechanism between 280°C and 450°C. Nonporous model copolymers poly(MA‐iPrA‐co‐EDMA) of similar composition, prepared by copolymerization of MA‐iPrA with EDMA, also decomposed by a one‐step mechanism as shown by TGA measurements.     

Synthesis,characterization and nucleolytic property of bis(N,N′-dimethylglycinato)copper(II)

Aquabis(N,N-dimethylglycinato)copper(II) dihydrate, [Cu(dmg)₂(H₂O)]·2H₂O, has been synthesized and characterized by elemental analysis, FT-IR, magnetic data, thermal analysis, solution UV-visible spectroscopy, X-ray crystal structure analysis and electrospray ionization mass spectroscopy. The square pyramidal copper(II) complex crystallizes in the orthorhombic space group P2₁2₁2₁. The complex cleaves circular plasmid DNA (pBR322) in the presence of H₂O₂. The extent of cleavage varies with the concentration range of the complex, the type of buffer used, pH of buffer and the concentration of H₂O₂. Hydroxyl radical scavenger can inhibit the nucleolytic ability of this complex.     

Electroanalytical performance of Cd(II) selective sensor based on PVC membranes of 5,5′‐(5,5′‐(benzo[c][1,2,5]thiadiazole‐4,7‐diyl)bis(thiophene‐5,2‐diyl))bis(N1,N1,N3,N3‐tetraphenylbenzene‐1,3‐diamine)

The construction and performance characteristics of polymeric membrane electrodes based on neutral ionophore 5,5′‐(5,5′‐(benzo[c][1,2,5]thiadiazole‐4,7‐diyl)bis(thiophene‐5,2‐diyl))bis‐(N1,N1,N3,N3‐tetraphenylbenzene‐1,3‐diamine) (L) for quantification of cadmium ions, are described. Effect of plastisizers dibutylpthalate (DBP), tri‐n‐butylphosphate (TBP), dioctylpthalate (DOP), o‐nitrophenyloctyl ether (o‐NPOE), 1‐chloronaphthalene (CN) and ionic additives sodium tetraphenylborate (NaTPB), potassium tetrakis p‐(chlorophenyl)borate (KTpClPB) was studied. Best performance was obtained with the membrane having a composition L?:?PVC?:?DBP?:?NaTPB?≡?2?:?37?:?59?:?2 (w/w; mg). The membrane electrode exhibits Nernstian response in the concentration range 6.3?×?10^?8 to 1.0?×?10?^?1?mol?L^?1 with detection limit 3.6?×?10^?8?mol?L^?1 and is not affected by H⁺ ions over a wide pH range 3.0–10.0. The electrode possess a fast response time of 10?s and shelf life period of 3 months. The analytical utility of the proposed electrode has demonstrated by its application in the determination of cadmium in water, medicinal plants and soil samples. It could also be used successfully as an indicator electrode in the potentiometric titration of Cd²⁺ with EDTA (ethylenediaminetetraacetic acid).     

Mesogenic and optical properties of α,α′‐bis(4‐alkoxyphenylethynyl)oligothiophenes

Liquid crystalline α,α′‐bis(4‐alkoxyphenylethynyl)oligothiophenes (bi‐ and ter‐thiophene) have been synthesized and their mesogenic behaviour and optical properties investigated. They all exhibited a nematic mesophase, and compounds with long alkoxy chains also showed lamellar phases. Increasing the number of thiophene units increased both the transition temperatures and the mesophase ranges. As for their optical properties, incorporating more thiophene units results in red‐shifted absorption and emission spectra, slightly enhanced quantum efficiency, and a larger Stoke's shift. Most importantly, in terms of the absorption and emission maxima, the incorporation of one 4‐alkoxyphenylethynyl moiety was found to be equivalent to adding one thiophene ring.     

Facile and Practical Synthesis of (R)‐6‐Br‐2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl

A new enantiopure 6‐monobromo‐substituted BINAP has been prepared via a one‐step nickel‐catalyzed coupling reaction in moderate yield. It is an important intermediate for asymmetric 2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl (BINAP) derivatives. Its structure was elucidated by NMR spectral and elemental analysis.     

Molecular Dimension and Interaction Parameters of Polyacrylamide in Water‐N,N‐Dimethylformamide Mixtures

The intrinsic viscosities [η] of polyacrylamide (PAM) having different average molecular weights are measured in various mixtures of water (good solvent) and N, N dimethyl formamide (DMF, nonsolvent) at different temperatures. The observed results show a significant variation of cosolvency as a function of solvent composition (?_DMF). The nature of curves in [η] vs. ?_DMF plot at different temperatures indicates the existence of two antagonistic effects. The unperturbed dimensions (K_θ) of the polymer are determined by a number of methods, which agree well with each other. The temperature coefficient of unperturbed dimension (K′), molecular extension factors (α_n), characteristic ratio (C_α) and chain rigidity (σ) are evaluated and the effects of temperature, solvent composition are discussed. The volume related parameter V_E and shape factor ν were also computed, which shows the shape of polymer molecules to be more or less spherical in solution.     

Synthesis and Crystallographic Study of1,6‐bis‐(N‐phenothiazinyl)‐2,4‐hexadiyne

1,6‐bis‐(N‐phenothiazinyl)‐2,4‐hexadiyne (I) was synthesized in high yield by oxidative coupling of N‐propargyl phenothiazine. Grown from methylene chloride‐hexane solution, I is a monoclinic crystal, space group C2/c a=14.9500(18) Å; b=13.5512(15) Å; c=12.0116(10) Å; β=102.628(9)° Å; V=2374.6(4) ų. The intermolecular distances and arrangement of I in the unit cell preclude the usual diacetylene reactivity. Nevertheless, heating of I at 145°C results in decomposition of I to phenothiazine and a dark brown solid. In addition, cation‐radicals of I were prepared by oxidation with nitrosonium tetrafluoroborate and iodine to give stable ion‐radical salts.     

One Facile Preparation of N‐Aroyl‐N′‐arylsulfonylhydrazines by Oxidation of Aromatic Aldehyde N‐Arylsulfonylhydrazones with bis(Trifluoroacetoxy)iodobenzene

N‐aroyl‐N′‐arylsulfonylhydrazines can be obtained by oxidation of aromatic aldehyde N‐arylsulfonylhydrazones with bis(trifluoroacetoxy)iodobenzene in acetone at room temperature in mild to good yields.     

Synthesis and Radical Polymerization of N‐[4‐N′‐(Phenylamino‐carbonyl)phenyl]maleimide and its Copolymerization with Methyl Methacrylate

A novel type of imide‐amide monomer, 4‐maleimidobenzanilide (MB) i.e., N‐[4‐N′‐(phenylaminocarbonyl)phenyl]maleimide was synthesized from maleic anhydride, p‐aminobenzoic acid and aniline. Radical polymerization of MB and its copolymerization with MMA (methyl methacrylate), initiated by AIBN, were performed in THF solvent at 65°C. Nine copolymer samples were prepared using different feed ratios of comonomers. All the polymer samples have been characterized by a solubility test, intrinsic viscosity measurements, FT‐IR and ¹H‐NMR spectral analysis, and thermo‐gravimetric analysis. The values of monomer reactivity ratios of MB‐MMA system (r₁, r₂) and the Alfrey‐Price parameters Q₁ and e₁ were determined.     

Synthesis of N,N′-Bis(arylsulfanyl)cyclohexa-2,5-diene-1,4-diimines and N,N′-(Cyclohexa-2,5-diene-1,4-diylidene)bis(arenesulfinamides)

Russian Journal of Organic Chemistry - Reactions of (chlorosulfanyl)benzenes with benzene-1,4-diamines afforded new N,N′-bis(arylsul­fanyl)cyclohexa-2,5-diene-1,4-diimines which were...     

N,N′-(1,2-phenylene)bis­(pyridine-2-carboxamide) and N,N′-(1,2-cyclohexanediyl)bis(pyridine-2-carbox­amide) toluene hemisolvate

The crystal structures of N,N′-(1,2-phenyl­ene)­bis­(pyridine-2-carbox­amide), C₁₈H₁₄N₄O₂, (I), and N,N′-(1,2-cyclo­hexane­diyl)­bis­(pyridine-2-carbox­amide) have been determined, the latter compound as the toluene hemisolvate, C₁₈H₂₀N₄O₂·0.5C₇H₈, (II). In (I), the benzene ring is nearly coplanar with one of the pyridine rings and forms a dihedral angle of 59.4 (1)° with the other. However, in (II), the dihedral angle of the two pyridine rings is 70.0 (1)°.     

Structure and Spectroscopic Characteristics of N,N′-bis(2-Hydroxy-3-methoxyphenylmethylidene)2,6-pyridinediamine

The Schiff base N,N-bis(2-hydroxy-3-methoxyphenylmethylidene)-2,6-pyridinediamine has been synthesized and characterized in the solid state and in solution using X-ray analysis, IR, UV/Vis, and NMR spectroscopy. Crystal data: C₂₁H₁₉N₃O₄, M _r = 377.39, orthorhombic, space group Pnc2, a = 4.9288(8), b = 8.8873(19), c = 20.870(5) Å, V = 914.19(20) ų, Z = 2, R = 0.0387, R _w = 0.0530, 1845 independent reflections, 778 with I > 2(I). There are two intramolecular hydrogen bonds O—H-N between the hydroxyl and imino groups of 2.622(3) Å. The enolimine form is found in the solid state and is also the predominant tautomeric form in solution. Comparison of the title compound with the structurally related N,N-bis(salicylidene)-2,6-pyridinediamine and N,N-bis(salicylidene)-2,3-pyridinediamine is given.     

The single-crystal electron spin resonance spectra of bis chloro bis(N,N′-substituted urea)oxovanadium(IV) compounds diluted in the corresponding tris-chloro bis(N,N′-substituted)urea indium(III) compounds

Single crystal ESR spectra of VOCl₂L₂ (where L = N, N, N′, N′-tetramethyl urea (tmu), N, N′-dimethylethyleneurea, N, N′-dimethylpropyleneurea, tris(dimethylamino)phosphincoxide) diluted in the corresponding Inøcl₃L₂, at Q-band frequencies are reported. The ESR data are consitent with C₂ point symmetry for VOCl₂(tmu)₂ whilst the other compounds approximate very closely to this point symmetry. A rotation of the g and A tensor axes in the plane perpendicular to the terminal VO vector fall in the range 8–15° for the four compounds studied. The spin Hamiltonian parameters for VOCl₂(tmu)₂, in conjunction with the published polarized electronic absorption spectra, have been analysed via angular overlap calculations. For VOCl₂(tmu)₂ unusual ligand hyperfine splittings were observed. These were analysed by spectrum simulation in terms of two equivalent chlorine atoms where the chlorine hyperfine and nuclear quadrupole tensors are of comparable magnitude.     

Vibrational study of N,N,N′,N′-tetramethyl-p-phenylenediamine and its radical cation

The i.r. and Raman spectra of N,N,N′,N′-tetramethyl-p-phenylenediamine and the perchlorate salt of its radical cation have been recorded. The frequencies of the fundamental vibrations of the neutral molecule and the radical ion have been computed using force constants transferred from smaller molecules. The observed spectral bands have been assigned and the ionization band shifts have been discussed. Most of the significant band shifts have been observed in the 1700-1300 cm⁻¹ range. The calculations showed that they are primarily due to the variation of the bond strengths of the ring CC and ring-N bonds.     

Physicochemical studies of the structure of N,N′-dinitrourea and its salts

The properties and behavior of dinitrourea and its potassium and dipotassium salts in different solvents have been studied by IR and UV spectroscopy. In different media, dinitrourea can exist in several tautomeric forms. An XRD study of the potassium and dipotassium salts of dinitrourea revealed a tendency toward equalization of the bond lengths of the C-N⁻-NO₂ fragments compared with those of C-NH-NO₂, which agrees with the results of quantum-chemical calculations.     

Synthesis,characterization and anti-microbial activity of poly(ethylene oxamide- N,N ′-disuccinate) and its polymer metal complexes

Poly(ethylene oxamide-N,N′-disuccinate), abbreviated as (PEODS), has been synthesized by condensation of oxamide-N,N′-disuccinic acid and 1,2-ethylene glycol. Coordination polymers were synthesized by the reaction of (PEODS) with hydrated acetates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). The resulting polyester-metal complexes were characterized by elemental analysis, UV-Visible, FT-IR, ¹H-NMR, ESR spectroscopy and magnetic susceptibilities. Thermal behavior of all the synthesized compounds revealed that polymer metal complexes are more stable than the polymeric ligand. In addition all the synthesized polymers were screened for anti-bacterial activity against B. subtelillisr, B. megaterium, S. aureus, E. coli, S. typhi, P.?aeruginosa, S. boydii and for antifungal activity against C. albicans, T. species, A. flavus, A. niger, F. species, M. species, and P. species by agar well diffusion methods. All the polymers showed good anti-bacterial and anti-fungal activity, which increased on coordination with the metal ions.     

Coordination compounds of copper and nickel with N,N′-[4,4′-(perfluoro-1,4-phenylene)bis(oxy)bis(4,1-phenylene)]-bis[2-(pyridin-2-ylmethylidene)hydrazinecarbothioamide] and its derivatives

N,N′-[4,4′-(Perfluoro-1,4-phenylene)bis(oxy)bis(4,1-phenylene)]bis[2-(pyridin-2-ylmethylidene)-hydrazinecarbothioamide] as well as its methyl and phenyl derivatives react with copper and nickel chlorides in ethanol to form coordination compounds. In the products, the hydrazinecarbothioamides act as doubly deprotonated bridging ligands. The prepared complexes have been found to inhibit in vitro the growth and propagation of the myeloid human leukemia HL-60 cancer cells at the 10^?5–10^?7 mol/L concentration.