Reaction of 2-chloro-3-(4-N,N-dimethylaminoanilino)-1,4-naphthoquinone with cyclic amines (piperidine,morpholine, and pyrrolidine)

It was shown that the reaction of 2-chloro-3-(4-N,N-dimethylaminoanilino)-1,4-naphthoquinone with piperidine in the absence of a solvent gives not only a product of replacement of the chlorine atom by a piperidino group, 3-(4-N,N-dimethylaminoanilino)-2-piperidino-1,4-naphthoquinone, but also 2-(4-N,N-dimethylaminoanilino)-1,4-naphthoquinone and 2-(4-N,N-dimethylaminoanilino-2-piperidino)-1,4-naphthoquinone. The latter compounds are the only reaction products formed in dimethyl sulfoxide. The reaction with morpholine occurs in a similar way, whereas that with pyrrolidine gives only a product of replacement of the chlorine atom by hydrogen.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2451–2454, December, 1995.     

Verfeinerung der Kristallstruktur von Kupfer(II)-hydroxichlorid,Cu(OH)Cl

The crystal structure of Cu(OH)Cl [a=5.555 (2) Å,b=6.671 (4) Å,c=6.127 (2) Å, =114.88 (3)°, space group P2_I/a,Z=4] was refined for 810 observed reflections with sin /0.80 Å^–1 toR=0.035. Crystals were synthesized under hydrothermal conditions. The copper atom is planar four coordinated by three oxygen atoms and one chlorine atom; two further chlorine atoms complete its coordination. The copper polyhedra share edges to build up sheets, which are connected by hydrogen bonds to the chlorine atoms of adjacent sheets.

     

Synthesis and Structure of Tri(p-tolyl)antimony Dichloride

Tri(p-tolyl)antimony dichloride was prepared by oxidation of tri(p-tolyl)stibine with chlorine or copper(II) chloride. As found by X-ray diffraction analysis, the antimony atom in tri(p-tolyl)antimony dichloride has the configuration of trigonal bipyramid with axially located chlorine atoms. The Sb-Cl and Sb-C distances are 2.476(2) and 2.104(7) Å, and the CSbC and ClSbCl angles are 120 and 180°, respectively.     

Coordination behaviour of Schiff base 2-acetyl-2-thiazoline hydrazone (ATH) towards cobalt(II), nickel(II) and copper(II)

The synthesis and characterization of Co(II), Ni(II) and Cu(II) complexes of 2-acetyl-2-thiazoline hydrazone (ATH) are reported. Elemental analysis, IR spectroscopy, UV–Vis–NIR diffuse reflectance and magnetic susceptibility measurement, as well as, in the case of copper complex EPR spectroscopy, have been used to characterize the complexes. In addition, the structure of [NiCl₂(ATH)₂] (2) and [{CuCl(ATH)}₂(μ-Cl)₂] (3) have been determined by single crystal X-ray diffraction. In all complexes, the ligand ATH bonds to the metal ion through the imine and thiazoline nitrogen atoms. X-ray data indicates that the environment around the nickel atom in 2 may be described as a distorted octahedral geometry with the metallic atom coordinated to two chlorine atoms, two thiazoline nitrogen atoms and two imino nitrogen atoms. With regard to 3, it can be said that its structure consists of dimeric molecules in which copper ions are bridge by two chlorine ligands. The geometry about each copper ion approximates to a distorted square pyramid with each copper atom coordinated to one thiazoline nitrogen atom, one imine nitrogen atom, one terminal chlorine ligand and two bridge chlorine ligands. In compound 3, magnetic susceptibility measurements in the temperature range 2–300 K show an intradimer antiferromagnetic interaction (J = −7.5 cm⁻¹).     

Thiosucres. III. Réactions du substituant (benzylthio)-acétyle. Communication préliminarie

Thiosugars. III. Some reactions of the (benzylthio)-acetyl substituent Preliminary Communication The (benzylthio)-acetyl substituent as found in 6-benzylthio-6-deoxy-1, 2-O-isopropylidene-3-O-methyl-α-D-xylo-hexofuranos-5-ulose ( 1 ) constitutes and useful synthon which can be transformed into ‘second generation’ synthons as, for example, the sulfylidene 10 or the chlorinated derivative 14 . S-Debenzylating C-acylation of 10 leading to 11 is described as well as the ring-forming condensation of 10 with the sulfene 12 . Depending on the nature of the nucleophile reacted with 14 , one can obtain the product of the substitution of the chlorine atom or of the chlorine atom and the benzylthio group or reactions taking place at both the carbonyl group and the terminal carbon atom, among them binucleophilic cyclizations. Some reactions of the conjugate base of 14 are also described.     

Structural researches on metal complexes with ligands containing the pyridoxal moiety: X-ray structure of chloro(N-pyridoxylidene-N′-salicyloylhydrazinato) copper(II) Monohydrate

Summary The x-ray crystal structure of the title complex is described Crystals are monoclinic, space groupP2₁/n, with unit-cell dimensions:a=18.070(2),b=13.471(2),c=6.788(2) Å,=94.70(1),Z=4. The structure was solved from diffractometer data by Patterson and Fourier methods and refined by least-squares techniques toR=5.0% for 2451 independent reflections. It consists of complex molecules, in which the copper atom square planar coordination comprises the chlorine atom, Cu-Cl=2.240(3) Å, and the organic ligand which acts as terdentate through the oxygen atom [Cu-O=1.948(3) Å] and a nitrogen atom, [Cu-N=1.933(5) Å] from the hydrazidic chain and the oxygen atom, [Cu-O = 1.894(4) Å] from the pyridoxal group.     

Synthesis, structure, and spatial arrangement of Si-substituted N-(dimethylsilylmethyl)imides

The synthesis of N-(chlorodimethylsilylmethyl)succinimide and N-(chlorodimethylsilylmethyl)-glutarimide by the reaction of the corresponding N-trimethylsilylimides with chlorodimethylsilane and by the reaction of unsubstituted imides with a mixture of hexamethyldisilazane with dimethylchloromethylchlorosilane is described. The formation of N-(chlorodimethylsilylmethyl)succinimide is followed by substitution by the silicon atom, which, depending on the reagent ratio, provides N-(dimethylsuccinimidomethyl)succinimide as the major or minor product. ¹H, ¹³C, and ²⁹Si NMR spectroscopy and X-ray diffraction analysis showed that the silicon atom in N-(chlorodimethylsilylmethyl)glutarimide is five-coordinate. By contrast, in N-(chlorodimethylsilylmethyl)succinimide and N-(dimethylsuccinimidomethyl)succinimide, according to NMR and X-ray diffraction data, the silicon atom is four-coordinate. Quantumchemical calculations by the AM1 method show that the molecular conformations of N-(chlorodimethylsilylmethyl)imides containing an intramolecular OSi bond are not energetically most favorable in the gas phase.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 10, 2004, pp. 1617–1623.Original Russian Text Copyright © 2004 by Pogozhikh, Ovchinnikov, Kramarova, Negrebetskii, Shipov, Albanov, Voronkov, Pestunovich, Baukov.This revised version was published online in April 2005 with a corrected cover date.     

Reactivity of methyl (3,6-dichloropyridazin-4-yl)acetate towards nucleophiles

Methyl (3,6-dichloropyridazin-4-yl)acetate (II), prepared from methyl (3,6-dihydroxypyrid-azin-4-yl)aeetate (1) by chlurination with phosphorus oxychloride, was used for studies of nucleo-philic displacement reactions and it has been found that only the chlorine atom at position 6 was displaced with hydrazine. With diluted hydrochloric acid both chlorine atoms were displaced with the 6-oxo isomer predominating. By turning the aromatic ring of pyridazine into an o-quinoid system, the chlorine atom at position 3 became mobile. Cyelization of (6-hydrazino-s-triazolo-[4,3-b ]pyridazin-7-yl)acetic acid hydrazide (XIX) gave 6-aminopyrrolo[3,2-e ]s-triazlo[ 4,3-b ]-pyridazm-7(8H)one (XXI).     

Quantum study on the electrocyclic reactions of CH2CHCHCHX (XH,F, Cl)

The microscopic mechanisms of the electrocyclic reactions for cis‐1,3‐butadiene and its monofluoro‐, monochloroderivatives have been studied by density functional theory (DFT), using the B3LYP method and 6‐311++G** basis sets. We optimized the geometric configurations of reactants, transition states, and products; verified all the probable transition states through vibrational analysis; and calculated the relative single‐point energies at the QCISD(T)/6‐311++G**//B3LYP/6‐311++G**. The results show that the monofluoro‐, monochloroderivatives of cis‐1,3‐butadiene both have two conformers; the reactant favors the electrocyclic reaction when one outboard hydrogen atom of the CH₂ groups is substituted by the fluorine or chlorine atom. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004     

New complexes derived from copper(II) salts and bis-N-(p-methoxyphenyl)-2, 5-furylideneimine

Summary Two new complexes derived from bis-N-(p-methoxyphenyl)-2, 5-furylideneimine(L) (1) and copper(II)[CuL₂](ClO₄)₂·4H₂O (2) and [(CuCl₂)₂L] (3), have been synthesized. The i.r. spectra of both complexes show that the ligand coordinatesvia oxygen and nitrogen. Spectral and magnetic properties are consistent with the formulation of (2) as an elongated tetragonal octahedral copper(II) structure and (3) as distorted square-planar copper(II) structure, where each copper atom is bonded to two chlorine, one oxygen and one nitrogen atoms, and two carbon and two copper atoms tetrahedrally surround the oxygen atom.     

Crystal structure of hexadimethylsulfoxidenickel(II) tetraisothiocyanatozincate

A new complex, hexadimethylsulfoxidenickel(II) tetraisothiocyanatozincate [Ni(DMSO)₆][Zn(NCS)₄](I), is synthesized. Its crystal structure is determined by X-ray diffraction analysis. Compound I forms light green, monoclinic crystals shaped like plates: a = 8.4358(8) Å ,b = 21.655(2) Å, c = 10.8351(8) Å = 105.162(7)°, V = 1910.4(3) ų, space group P2₁/m, Z = 2, (calcd) = 1.434 g/cm ³ , µ= 1.699mm ^–1. The Zn atom has a tetrahedral environment, while the Ni atom has an octahedral environment.Translated from Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 939–942.Original Russian Text Copyright © 2004 by Cherkasova, Tsalko.     

Palladium(II) and platinum(II) complexes of Schiff bases derived from 2,6-diacetylpyridine and S-methyldithiocarbazate and the X-ray crystal structure of the [Pd(mdapsme)Cl] complex

Condensation of 2,6-diacetylpyridine (dap) with S-methyldithiocarbazate (smdtc) in a 1:2 molar ratio yields a bicondensed pentadentate Schiff base (H₂dapsme) which reacts with K₂MCl₄ (M = Pd^II, Pt^II) giving stable complexes of empirical formula, [M(dapsme)] · 0.5Me₂CO. These complexes have been characterized by a variety of physico-chemical techniques. Condensation of dap with smdtc in a 1:1 molar ratio also yields the bicondensed Schiff base (H₂dapsme) as the major product, but a mono-condensed one-armed Schiff base (Hmdapsme) is also obtained as a minor product. The latter reacts with K₂PdCl₄ in an EtOH–H₂O mixture yielding a crystalline complex of empirical formula, [Pd(mdapsme)Cl], the crystal structure of which has been determined by X-ray diffraction. The complex has a distorted square-planar structure in which the ligand is coordinated to the palladium(II) ion as a uninegatively charged tridentate chelating agent via the pyridine nitrogen atom, the azomethine nitrogen atom and the thiolate sulfur atom; the oxygen atom of the acetyl group does not participate in coordination.     

Crystallographic report: Bis{4‐[N,N‐bis(2‐cyanoethyl)amino]pyridine} dichlorozinc(II)

In (C₁₁H₁₂N₄)₂ZnCl₂, the zinc(II) center is coordinated by the pyridine nitrogen atoms of two 4‐[N,N‐bis(2‐cyanoethyl)amino]pyridine ligands and two chlorine atoms in a tetrahedral geometry. Copyright © 2004 John Wiley & Sons, Ltd.     

Halogenation of dichloro- and dibromovinyl(phenyl) sulfides

Bromination of 2,2-dichlorovinyl(phenyl) sulfide with bromine afforded a product that, upon heating or addition of zinc, cleaved the bromine to form the original sulfide. Chlorination of 2,2-dibromovinyl(phenyl) sulfide with chlorine resulted in substitution of a bromine atom by chlorine and/or hydrogen at the double bond as well as cleavage of the C-S bond to form polyhaloethenes, polyhalosulfides, and chlorinated dithioethenes. The chlorine addition product was absent.Irkutsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, Irkutsk 664033. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 955–957, April, 1992.     

Reaction of N-(Trichloroacetyl)trichloroacetimidoyl Chloride with Phosphites

N-(Trichloroacetyl)trichloroacetylimidoyl chloride reacts with trialkyl phosphites with substitution of the imidoyl chlorine atom and formation of C-phosphorylated heterodienes. The reaction with triphenyl phosphite or o-phenylene diethylphosphoroamidite proceeds as [4+1]-cycloaddition to give mono- or spirocyclic oxazaphospholines with the five-coordinate phosphorus atom. Dialkyl or diphenyl hydrogen phosphites add across the C = N bond of imidoyl chloride to give labile N-(-phosphorylated) trichloroacetamides.     

Crystallographic report: [(1,3‐Bis(4‐pyridyl)propane)(diaqua)zinc(II)] diperchlorate dihydrate

Four ligands of 1,3‐bis(4‐pyridyl)propane and two water molecules are coordinated to the zinc(II) atom so that the coordination geometry closely resembles a trans‐N₄O₂ octahedral environment. Copyright © 2004 John Wiley & Sons, Ltd.     

Hydroalumination of a Chlorotrialkynylsilane: Spontaneous Stepwise 1,3‐Dyotropic Rearrangement via an Intermediate Silyl Cation

A new functionalised alkynylsilane, Cl‐Si(C?C‐CMe₃)₃ ( 3 ), was obtained by a facile multistep synthesis. Treatment of 3 with equimolar quantities of the hydrides H‐M(CMe₃)₂ (M=Al, Ga) gave the mixed alkenyl‐di(alkynyl)silanes, in which the chlorine atom adopts a bridging position between the aluminium and silicon atoms. Dual hydrogallation of 3 resulted in the formation of a di(alkenyl)‐alkynylsilane containing two gallium atoms, one of which is coordinated to the chlorine atom, and the second is bonded to the α‐carbon atom of the remaining alkynyl group. A tert‐butylsilane was unexpectedly formed by a unique 1,3‐dyotropic chlorine–tert‐butyl exchange for the corresponding dialuminium compound. One aluminium atom is bonded to a tert‐butyl group, a terminal chlorine atom and the α‐carbon atom of the ethynyl moiety; the second is coordinatively unsaturated, with two terminal tert‐butyl substituents. High‐level quantum‐chemical calculations favour a stepwise dyotropic rearrangement with an intermediate cationic silicon species over a simultaneous tert‐butyl–chlorine migration via a five‐coordinate silicon atom in the transition state.     

Crystallographic report: Bis(4‐nitrobenzoato)bis(pyridine)zinc(II)

The molecular structure of [Zn(O₂CC₆H₄NO₂‐p)₂(pyridine)₂] exhibits a distorted N₂O₂ tetrahedral geometry around the zinc atom owing to the presence of monodentate p‐nitrobenzoate ligands; the molecule has twofold symmetry. Copyright © 2004 John Wiley & Sons, Ltd.     

Crystallographic report: Chlorobis(tripyridyldiamine)cadmium(II) nitrate

The Cd(II) atom in [(tpda)₂CdCl]NO₃, is octahedrally coordinated to one chlorine and five pyridyl‐nitrogen atoms. The coordination cations and nitrate anions are connected by multiple hydrogen bonds, affording a two‐dimensional structure. Copyright © 2005 John Wiley & Sons, Ltd.     

Crystal structure and spectroscopic properties of trans-dichlorobis(1,3-propane-diamine)chromium(III) perchlorate

The crystal structure of trans-[Cr(tn)₂Cl₂]ClO₄ (tn = 1,3-propanediamine) is determined by a single-crystal X-ray diffraction study at 185 K. The Cr atom is in a slightly distorted octahedral environment coordinated by four nitrogen atoms of two tn ligands and two chlorine atoms in trans position. The orientations of two six-membered rings in the complex cation are in an anti chair-chair conformation with respect to each other. The mean Cr-N(tn) and Cr-Cl bond lengths are 2.0862(2) ? and 2.3112(6) ? respectively. The ClO₄⁻ anions have a slightly distorted tetrahedral geometry with Cl-O lengths and O-Cl-O angles influenced by the hydrogen bonding. The crystal packing is stabilized by several hydrogen bonds. The infrared and electronic absorption spectral properties are also described along with the results of X-ray crystallography.