Directed Aminomethylation of Pyrrole,Indole, and Carbazole with <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N′</Emphasis>,<Emphasis Type="Italic">N′</Emphasis>-Tetramethylmethanediamine

Catalytic aminomethylation of pyrrole and indole with N,N,N′,N′-tetramethylmethanediamine in the presence of 5 mol % of ZrOCl₂·8H₂O proceeds selectively at the positions 2, 5 of pyrrole and 1, 3 of indole. Carbazole under the same conditions affords 3-formyl-9-aminomethyl derivative. The reaction in the presence of 5 mol % of K₂CO₃ occurs as monoaminomethylation: for pyrrole at the position 2, for indole at the position 3, and for carbazole at the nitrogen atom of the substrate. Water-soluble 1,1′-(1H-pyrrole-2,5-diyl)bis(N,N-dimethylmethanamine) exhibits a fungistatic activity with respect to phytopathogenic fungi Rhizoctonia solani.     

<Emphasis Type="Italic">N</Emphasis>′-tetrazolylmethoxyl derivatives of <Emphasis Type="Italic">N</Emphasis>-methyldiazene <Emphasis Type="Italic">N</Emphasis>-oxides

A preparation method was developed for previously unknown tetrazole derivatives containing in the 1, 2, and/or 5 positions of the tetrazole ring N-methyldiazene-N-oxide-N′-oxymethyl groups.     

1,3-Diamino-2-Hydroxypropane-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-Tetraacetic Acid: Crystal and Molecular Structures

The synthesis, IR spectroscopic study, and X-ray diffraction analysis (CIF file CCDC no. 1574078) are carried out for 1,3-diamino-2-hydroxypropane-N,N,N′,N′-tetraacetic acid (I). The structural units of a crystal of compound I are (H_4.5HPdta)^0.5– anions, (H_5.5HPdta)^0.5+ cations, and molecules of water of crystallization joined by a branched network of hydrogen bonds: strong intermolecular O–H…O and intramolecular N–H…O bonds.     

Complex formation of magnesium and calcium ions with trimethylenediamine-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>’,<Emphasis Type="Italic">N</Emphasis>’-tetraacetic acid

Stability constants and heat effects of the formation reactions of magnesium and calcium trimethylenediaminetetraacetates at 298.15 K and ionic strength of 0.1, 0.5, and 1.0 (mol/L KNO₃) have been determined by means of potentiometry and calorimetry. Standard thermodynamic parameters (log K⁰, Δ_rG⁰, Δ_rH⁰, and Δ_rS⁰) of the studied equilibriums have been determined.     

<Emphasis Type="Italic">N</Emphasis>-arylsulfanyl-<Emphasis Type="Italic">N</Emphasis>-arylsulfonyl(acyl)-<Emphasis Type="Italic">N</Emphasis>′-phenylthiourea sodium salts

Reactions of N-arylsulfonyl(acyl)arenesulfenamide sodium salts with phenyl isothiocyanate afforded N-arylsulfanyl-N-arylsulfonyl(acyl)-N-phenylthioura sodium salts which were found to increase thermal stability of finely dispersed poly(vinyl chloride).Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 10, 2004, pp. 1532–1535.Original Russian Text Copyright © 2004 by Koval, Oleinik.     

Thermophysical properties of <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-dimеthylacetamide mixtures with <Emphasis Type="Italic">n</Emphasis>-butanol

The refraction, dielectric, viscosity, density, data of the binary mixtures of N,N-dimethylacetamide (DMA) with n-butanol at 308.15 and 313.15 K. The measured parameters used to obtain derived properties like Bruggeman factor, molar refraction and excess static dielectric constant, excess inverse relaxation time, excess molar volume and excess viscosity, excess molar refraction. The variation in magnitude with composition and temperature of these quantities has been used to discuss the type, strength and nature of binary interactions. Results confirm that there are strong hydrogen-bond interactions between unlike molecules of DMA+ n-butanol mixtures and that 1: 1 complexes are formed and strength of intermolecular interaction increases with temperature.     

Synthesis and structure of the cobalt(II) coordination compounds with <Emphasis Type="Italic">N,N</Emphasis>-dimethyl-<Emphasis Type="Italic">N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-dimethylthiocarbamoylsulfenamide

The CoLX₂ complexes were obtained by the reaction of N,N-dimethyl-N′,N′-dimethylthio-carbamoylsulfenamide (L) with CoX₂ (X = Cl, Br, I, NCS). The complexes were investigated by elemental and X-ray analysis, IR, ¹H NMR, and electron spectroscopy, conductometry, magnetochemistry, thermogravimetry. It is found that these compounds are high-spin complexes of pseudotetraedral structure with bidentate coordination of L through the thione sulfur atom and sulfenamide nitrogen atom.     

SBR composites reinforced with <Emphasis Type="Italic">N</Emphasis>-isopropyl-<Emphasis Type="Italic">N</Emphasis>′-phenyl-<Emphasis Type="Italic">P</Emphasis>-phenylenediamine-modified clay

SBR compounds including the N-isopropyl-N’-phenyl-p-phenylenediamine-modified clay(organoclay) were prepared.Effects of modified clay and antioxidant(IPPD) contents on mechanical and rheological properties of SBR composites were studied.FTIR results confirmed that the clay was chemically modified by IPPD and changed into an organoclay.X-ray diffraction(XRD) results confirmed the increase in interlayer distance of the clay due to the insertion of IPPD.Rheological and cure characteristics of SBR compounds were determined using RPA(Rubber Process Analyzer) and rheometer.Scorch time and cure time of SBR compounds decreased with introduction of the organoclay.Mechanical properties and heat aging resistance of the SBR composites were improved significantly by incorporation of the organoclay.     

Adsorption of <Emphasis Type="Italic">N</Emphasis>-hydrocinnamoyl-<Emphasis Type="Italic">N</Emphasis>-phenylhydroxylamine on pure minerals

Equilibrium adsorption studies of N-hydrocinnamoyl-N-phenylhydroxylamine (HCNPHA) on galena, sphalerite, pyrite, chalcopyrite and quartz at pH 9 and 10 are reported. All adsorption isotherms followed Langmuir model, however, Freundlich type was observed for quartz. As HCNPHA is a strong chelating agent, formation of monolayers by chemisorption appeared to be the most probable mechanism of adsorption on the base-metal sulphide minerals. Specific adsorption of HCNPHA on iron containing minerals, namely, chalcopyrite and pyrite, was about three times that on galena and sphalerite, and specific adsorption on quartz was the lowest amongst the minerals studied. Specific adsorptions (in μmol/g) of HCNPHA on the minerals at pH 9 are: sphalerite: 30.5; galena: 26.9; chalcopyrite: 112.3; pyrite: 145.4; quartz: 2.9. Compared to pH 9, specific adsorption of HCNPHA on the minerals decreased at pH 10, indicating hydroxylation of mineral sites due to higher hydroxide ion concentration at pH 10. A spectral-colorimetric procedure was developed for the quantitative estimation of HCNPHA. Due to deprotonation of hydroxamic acids direct estimation using UV absorption was not possible. Hence, complexation of HCNPHA with Fe³⁺ was used to develop a purple coloured complex that absorbs in the visible region with λ _max=500 nm. Change in concentration of HCNPHA was measured from absorbance of the HCNPHA- Fe³⁺ complex at 500 nm.     

Converting dipyrrinones to lactim ethers to fluorescent <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-difluoroboryl derivatives

A high-yield straightforward conversion of lactams to lactim ethers is shown by the conversion of (10H)-dipyrrin-1-ones to (11H)-dipyrrin-1-ol methyl and ethyl ethers in 90% yield from heating in neat trimethyl or triethyl phosphite at 160°C. Unlike the parent dipyrrinones, which form intermolecularly hydrogen-bonded dimers in CHCl₃, their lactim ethers are shown to be monomeric by vapor pressure osmometry. The latter react with boron trifluoride etherate to N,N′-bridged BF₂ derivatives that exhibit strong fluorescence (φ_F 0.6–0.8) near 535 nm. X-Ray crystal structures were obtained of the lactim ethyl ether of kryptopyrromethenone and the BF₂ derivative of the lactim ethyl ether 2,3-diethyl-7,8-dimethyl-(10H)-dipyrrin-1-one. Correspondence: David A. Lightner, Department of Chemistry, University of Nevada, Reno, Nevada 89557-0020 USA.     

NMR Study of the graphite–<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-dimethylformamide system after ultrasonication

A suspension formed as a result of ultrasonication of a mixture of graphite with N,N-dimethylformamide has been studied by ¹H NMR spectroscopy. The dependence of the width of the ¹H NMR signal on the N,N-dimethylformamide content of the suspension has been determined.     

Extraction-photometric determination of <Emphasis Type="Italic">N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-dialkylbenzhydrazides as its complexes with copper

A procedure for extraction-photometric determination of N′,N′-dialkylbenzhydrazides has been proposed; the procedure is based on the formation of its colored complex with copper (II) followed by extraction with p-xylene and absorbance measurements at 460 nm (0.1–0.4 mmol of analyte in the sample) or at 330 nm (0.005–0.025 mmol of analyte in the sample).     

Synthesis of <Emphasis Type="Italic">N</Emphasis>-nitro-<Emphasis Type="Italic">N</Emphasis>′-(trimethylsilyl)carbodiimide

Nitration of N,N′-bis(trimethylsilyl)carbodiimide with N₂O₅ or (NO₂)₂SiF₆ afforded N-nitro-N´-(trimethylsilyl)carbodiimide, the first representative of N-nitro carbodiimides. Its further nitration led to the release of CO₂, which is presumably formed in the course of N,N´-dinitrocarbodiimide decomposition. The reactions of N-nitro-N´-(trimethylsilyl)carbodiimide with nucleophiles take place both at the tri methylsilyl group (for example, with NH₃) to give nitrocyanamide salts and at the carbodiimide C atom (for example, with Et₂NH) to give the corresponding nitroguan idines.     

Novel <Emphasis Type="Italic">β</Emphasis>-<Emphasis Type="Italic">N</Emphasis>-acetylglucosaminidases from <Emphasis Type="Italic">Vibrio harveyi 650</Emphasis>: Cloning,expression, enzymatic properties,and subsite identification

Background  

Since chitin is a highly abundant natural biopolymer, many attempts have been made to convert this insoluble polysaccharide into commercially valuable products using chitinases and β-N-acetylglucosaminidases (GlcNAcases). We have previously reported the structure and function of chitinase A from Vibrio harveyi 650. This study t reports the identification of two GlcNAcases from the same organism and their detailed functional characterization.     

Three New <Emphasis Type="Italic">in situ</Emphasis> Syntheses of <Emphasis Type="Italic">N</Emphasis>-Acyl-α-triphenylphosphonioglycinates

Summary. N-Acyl--hydroxyglycinates were transformed into N-acyl--triphenylphosphonioglycinates by (i) phosphorylation with Ph ₃PBr₂ in the presence of Et ₃N or (ii) in reaction with DCC and Ph ₃P·HBF₄ in the presence of catalytic amounts of Ph ₃P as well as (iii) by a new kind of Mitsunobu reaction with Ph ₃P·HBF₄ as a nucleophile conjugated acid. The N-acyl--triphenylphosphonioglycinates can be effectively used without isolation for a nucleophilic displacement of the triphenylphosphonium group to obtain corresponding -substituted -amino acid derivatives.     

Dirhenium Compounds Supported by <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis><Emphasis Type="BoldItalic">′</Emphasis>-Dimethylbenzamidinate: Formation of Linear Polymers via Axial Ligation

The reaction between Re₂(DMBA)₄Cl₂ and NaN(CN)₂ resulted in Re₂(DMBA)₄(N(CN)₂)₂ (1a), where DMBA is N,N′-dimethylbenzamidinate. Molecular compounds Re₂(DMBA)₄(ReO₄)₂ (1b) and Re₂(DMBA)₄(OP(O)(OH)Ph)₂ (1c) were obtained through the reactions between Re₂(DMBA)₄(NO₃)₂ and the respective monoanion. The dirhenium(III) coordination polymers [Re₂(DMBA)₄(μ-O,O′-WO₄)·2H₂O]_∞ (2a), [Re₂(DMBA)₄(μ-O,O′-MoO₄)·2H₂O]_∞ (2b), and [Re₂(DMBA)₄(μ-O,O′-1,4-(O₂C)₂C₆H₄)·2H₂O]_∞ (2c) were similarly prepared through slow diffusion of Re₂(DMBA)₄(NO₃)₂ in acetonitrile into aqueous solution containing the respective dianion. All new compounds were characterized with single crystal X-ray diffraction, which revealed the retention of the essential structural features of Re₂(DMBA)₄ unit upon the formation of coordination polymers.     

Pseudo-Polymorphs of <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-Bis(4-nitrophenyl)-2,6-Pyridinedicarboxamide

Three pseudo-polymorphs of N, N′-bis(4-nitrophenyl)-2,6-pyridinedicarboxamide 1 were characterized by X-ray crystallography. The C–H ⋅s O hydrogen bond was found to contribute significantly to the assembly of this host. With the variation of the guest, the host changed the molecular conformation and the supramolecular synthons. In all three cases concerned, the solvent guests were bonded through direct host-guest interaction and accommodated in the voids formed by the assembly of the host.     

Novel mixed-ligand complexes of coumarilate/<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-diethylnicotinamide with some transition metals

Coordination complexes of transition metal cations (Co^II, Ni^II, Cu^II and Zn^II) containing coumarilate and N,N′-diethylnicotinamide were synthesized. The structural characterization and thermal behaviour analysis of novel samples synthesized were conducted through elemental analysis, magnetic susceptibility, solid-state UV–Vis, direct and injection probe mass spectra, FTIR spectra, thermoanalytic TG-DTG/DTA and single crystal X-ray diffraction methods. The structural details of single crystals of [Co(dena)₂(H₂O)₄](coum)₂ (I) and [Cu(coum)₂(dena)₂(H₂O)₂] (III) complexes were resolved completely. Moreover, the results of analysis obtained for [Ni(coum)₂(dena)₂(H₂O)₂] (II) and [Zn(dena)₂(H₂O)₄](coum)₂ (IV) complexes were interpreted considering the samples with crystal structures defined and made assumptions about the structural details. It was determined that the complex of Co^II metal cation has salt-type structure and the coordination number of metal is accomplished to six as the sum of 4 mol of water and also 2 mol of N,N′-diethylnicotinamide ligands in trans position located within the coordination sphere. It was observed that 2 mol of coumarilate anions are located outside the coordination sphere and have stabilized to the charge (2+) of metal. The Cu^II complex has totally molecular structure, and the coordination sphere of metal cation was 6 as the sum of 2 mol of water, 2 mol of N,N′-diethylnicotinamide and 2 mol of monoanionic monodentate coumarilate ligands. All ligands have been located in –trans position. The geometry of both complex structures is distorted octahedral. It is assumed that the Ni^II complex structure is isostructural with Cu^II complex structure and also does Zn^II complex with Co^II structure. It was determined that the decomposition products obtained from thermal analysis are the oxides of related metal cations.     

Synthesis of 20<Emphasis Type="Italic">S</Emphasis>-protopanaxadiol <Emphasis Type="Italic">β</Emphasis>-D-galactopyranosides

20S-Protopanaxadiol (3β,12β,20S-trihydroxydammar-24-ene) 3-, 12-, and 20-O-β-D-galactopyranosides were synthesized for the first time. Condensation of 12β-acetoxy-3β,20S-dihydroxydammar-24-ene (1) and 2,3,4,6-tetra-O-acetyl-α-D-galactopyranosylbromide (α-acetobromogalactose) (2) under Koenigs–Knorr conditions with subsequent removal of the protecting groups resulted in regio- and stereoselective formation of 20S-protopanaxadiol 3-O-β-D-galactopyranoside, an analog of the natural ginsenoside Rh₂. Glycosylation of 12β,20S-dihydroxydammar-24-en-3-one (5) by 2 with subsequent treatment of the reaction products with NaBH₄ in isopropanol and deacetylation with NaOMe gave 20S-protopanaxadiol 12- and 20-O-β-Dgalactopyranosides.     

<Emphasis Type="Italic">β</Emphasis>-Chloro-<Emphasis Type="Italic">α</Emphasis>,<Emphasis Type="Italic">β</Emphasis>-unsaturated carbonyls as convenient precursors of highly substituted benzenes

The Diels–Alder reactions of three β-chloro-α,β-unsaturated carbonyl compounds 1–3 with different dienes were carried out to afford highly functionalized cyclohexenes 4–9, bearing quaternary centers, in good yields. These cycloadducts (CAs) undergo dehydrochlorination with subsequent aromatization in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene DBU to produce new substituted benzenes 11–14. Compound 10 is the product of lactonization and removal of an HCl molecule from compound 7. All products were characterized by NMR, IR, elementary analysis and some of them by MS. Structure assignments of isomers were carried out on the basis of NMR chemical shifts and coupling constants using 1D, 2D and heteronOe NMR techniques.