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.     

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.     

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.     

Improved Synthesis of C 2‐Symmetric 4,4′‐α,ω‐Alkylenedioxy‐bis(3‐methoxybenzaldehydes)

Abstract

An improved Williamson synthesis of C ₂‐symmetric 4,4′‐(α,ω‐alkylenedioxy)‐bis(3‐methoxybenzaldehydes) from vanillin is described. These dialdehydes are often insoluble in cold acetone, which renders their purification especially facile.     

Dye Binding Characteristics of N,N′‐Methylene‐bis‐acrylamide (NNMBA)‐Crosslinked Polyacrylamide‐Supported Amine and its Photooxidizing Ability

The dye binding characteristics of 8 mol% NNMBA‐crosslinked polyacrylamide‐supported amine is investigated with Rose Bengal (RB), Methyl Orange (MO), Methylene Blue (MB) and Methyl Red (MR). The influence of the concentration of dye solution on dye binding, time course of dye binding and characterization were explored. It is observed that binding is higher in the case of Rose Bengal and dye binding depends on the polarity, as well as the size of the dye molecule. The photooxidation property of polymer bound RB was investigated towards the oxidation of benzoin to benzil. RB bound polymer acts as an efficient heterogenous photooxidizing agent.     

Reaction of Imines with 5,5‐Dimethyl‐1, 3‐cyclohexandione

The reaction of imines 1 with 5,5‐dimethyl‐1,3‐cyclohexandione 2 in methanol was investigated. When the reaction was carried out without a catalytic amount of molecular iodine, ring‐opening derivatives of xanthenediones 3 were obtained in high yields. On the other hand, when molecular iodine and a catalytic amount of zinc powder were employed as the catalyst, xanthenediones derivatives 4 were obtained with excellent yields.     

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.     

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.     

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.     

Formation of 1,2,5‐Oxadiazole,Isoxazole, Isothiazole, 1,2,3‐Triazole,and Pyrrole Rings from N‐(5,5‐Dimethyl‐3‐oxocyclohexenyl)‐S,S‐diphenylsulfilimine

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.     

Efficient Synthesis of 1‐(5′‐Acylamino‐1′,3′,4′‐thiadiazol‐2′‐yl)‐4‐acyl‐thiosemicarbazides

Acyl chlorides reacted with ammonium thiocyanate and carbonic dihydrazide under phase‐transfer catalysis to first afford 2,2′‐bis(acylaminothiocarbonyl)‐carbonic dihydrazides, which further cyclized in the presence of glacial acetic acid to efficiently give 1‐(5′‐acylamino‐1′,3′,4′‐thiadiazol‐2′‐yl)‐4‐acyl‐thiosemicarbazides in high yield.     

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)°.     

PVT properties of N,N,N′,N′-Tetraoctyl-3-oxapentanediamide (TODGA)

N,N,N??,N??-Tetraoctyl-3-oxapentanediamide (TODGA) is a versatile extractant for partitioning of fission products from highly active raffinate wastes. Its PVT properties are not available in literature. In this work, PVT properties of TODGA, estimated using group contribution method, are reported. A corresponding-states based equation as well as Wagner constants were also reported in the range of 273.15?K to critical temperature.     

Microwave‐Assisted Synthesis of N,N′‐Disubstituted Acetamidine Ligands

Under microwave activation, triethylorthoacetate reacts with the substituted anilines in the presence of acetic acid as a catalyst, producing acetamidine in moderate to high yields. The X‐ray structures of the new amidines, N,N′‐bis(3,5‐dimethylphenyl)‐acetamidine and N,N′‐bis(p‐tolyl)acetamidine, are also reported, revealing polymeric chains supported by intramolecular H‐bonds.     

Smectogenic properties of N,N′‐bis[(2‐hydroxy‐4‐alkoxyphenyl)methylene]benzene‐1,4‐diamine liquid crystals with double lateral H‐bonds

A series of eight liquid crystalline compounds, N,N′‐bis[(2‐hydroxy‐4‐alkoxyphenyl)methylene]benzene‐1,4‐diamines, has been synthesized and characterized. These homologous compounds differ in the length of terminal alkyl group C _n H_2n+1 wherein n is an even number ranging from 4 to 18. The spectroscopic techniques, FTIR, ¹H NMR and ¹³C NMR, were employed to characterize the molecular structure. The transition temperatures of all the title compounds and their mesophases were studied by differential scanning calorimetry and polarizing microscopy. All the compounds were smectogenic, exhibiting both tilted and non‐tilted molecular orientation in their smectic phases. Further investigation to ascertain the anisotropic nature of subphases within the smectogenic region was carried out using X‐ray diffraction.     

Spectroscopic and extraction studies of new transition metal complexes with N,N ′- bis (2-aminothiophenol)-1, 4- bis (2-carboxaldehydephenoxy)butane

Metal complexes of La(III), Cu(II) and Ni(II) with a thio Schiff base derived from 1,4-bis(2-carboxaldehydephenoxy)butane and 2-aminothiophenol have been synthesized in absolute ethanol and characterized by microanalytical data, magnetic measurements, ¹H NMR, ¹³C NMR, UV-visible, IR-spectra, mass spectra and conductance measurements. The extractability of divalent cations was evaluated as a function of relationship between distribution ratios of the metal and pH or ligand concentration. The highest extraction percentage of Cu⁺² and Ni⁺² were at pH 7.0 and 6.4, respectively. The ligand can effectively be used in solvent extraction of copper(II) and nickel(II) from aqueous phase to organic phase.     

Asymmetric Synthesis of (2S)‐1‐(3,4‐Dihydroxyphenoxy)‐3‐(3,′4′‐Dimethoxyphenoxy) Ethylamino‐2‐propanol hydrochloride (RO363)

Enantiomerically pure (S)‐RO363 was synthesized by using (R,R) Salen Co(III) complex for the resolution of terminal epoxide. The hydrolytic kinetic resolution process was carried out at room temperature in excellent enantioselectivity. The method can be applied for large‐scale preparation of (S) RO363.     

Application of Sulfinyl bis(2,4‐dihydroxythiobenzoyl) in the Synthesis of N‐Substituted 2‐Amino‐5‐(2,4‐dihydroxyphenyl)‐1,3,4‐thiadiazoles

One‐stage synthesis of N‐substituted 2‐amino‐5‐(2,4‐dihydroxyphenyl)‐1,3,4‐thiadiazoles is described. The compounds were prepared by the reaction of the sulfinyl bis(2,4‐dihydroxythiobenzoyl) (STB) with 4‐substituted 3‐thiosemicarbazides. STB was obtained from 2,4‐dihydroxybenzenecarbodithioic acid and thionyl dichloride. The structure of compounds was confirmed by IR, ¹H NMR, ¹³C NMR, and EI‐MS data.     

Application of a Model Building Approach to Molecular Mechanics (MM3) for Calculating Low‐Energy Conformations of Tetra‐O‐Acyl‐N,N′‐Dialkyl‐D‐Glucaramides

A model building approach was used in conjunction with the MM3 molecular mechanics program to find the low‐energy conformations of three tetra‐O‐acyl‐N,N′‐dimethyl‐d‐glucaramide molecules: tetra‐O‐propanoyl‐(2), 2‐methylpropanoyl‐(3) and 2,2‐dimethylpropanoyl‐N,N′‐dimethyl‐d‐glucaramide (4), and tetra‐O‐acetyl‐N,N′‐dihexyl‐d‐glucaramide (5). A set of models was chosen for calculation of the low‐energy conformations of parent tetra‐O‐acetyl‐N,N′‐dimethyl‐d‐glucaramide (1), with additional models required to simulate conformationally more complex diamides 2–5. The dominant low‐energy conformations of 2 and 3 were very similar to that from 1, whereas very sterically constrained 4, with four bulky pendant O‐2,2‐dimethylpropanoyl groups, and 5, with terminal n‐hexyl groups, adopted different conformations. Stereoregular alternating head tail–tail head and repeating head tail–poly(hexamethylene 2,3,4,5‐tetra‐O‐acetyl‐D‐glucaramide) oligomers were graphically generated to provide some insight into the possible conformations of the actual acylated polyamides in nonpolar solution.     

Oxidative Cyclization of Aromatic Aldehyde N‐Acylhydrazones by bis(Trifluoroacetoxy)iodobenzene

Aromatic aldehyde N‐acylhydrazones were oxidized into 2,5‐disubstituted 1,3,4‐oxadiazoles with bis(trifluoroacetoxy)iodobenzene in CHCl₃ or DMSO at room temperature in good to excellent yields.