Synthesis and crystal structure of a novel two-dimensional network complex [Mn(O2CCH2Cl)2(phen)] n

A novel two-dimensional network manganese(II) polymer complex [Mn(O₂CCH₂CI)₂-(phen)] _n has been synthesized and characterized by elemental analysis and IR spectrum. The crystal structure of title complex has also been determined, which is in monoclinic of a space group P2₁/c with the following unit cell parameters at 294K:a =1.9738 (4) nm,b=1.1384 (2) nm,c =0.74915(14) nm,V = 1.6795(5) nm³, Z= 2.

     

Crystal structure of tris(2-pyridylthio-2-pyridinium)pentaisothiocyanato-dioxouranate(VI)

Summary The crystal structure of [DPSH] ₃ ⁺ [UO₂[NCS)₅]^3– (DPSH = 2 pyridylthio-2-pyridinium) has been determined by standard methods using diffractometer data. Crystals are monoclinic, space groupP2₁/a, witha=33.16 (3),b=16.68(2),c=7.85(1) Å, and=97.3(1); D_c=1.65 g · cm^–3 for Z=4. The structure has been refined to R=5.8% by least squares methods. Five thiocyanate groups are equatorially bonded to the linear uranyl group. The mean of the five U-N, N-C, and C-S bond distances are 2.45, 1.17, and 1.59 Å respectively. The protonated DPS molecules have the N,N-inside conformations.     

Polarographic behaviour of 2-benzilidenimino-benzohydroxamic acid (2-BIBH) and 2-BIBH-Mo(VI) system

The polarographic behaviour of 2-benzilideniminobenzohydroxamic acid (2-BIBH) solutions and of 2-BIBH solutions in the presence of Mo(VI) have been studied by using differential pulse polarography and cyclic voltammetry. The polarographic characteristics of the resulting waves have been studied and possible mechanisms of the processes involved have been proposed. A linear relationship has been observed betweenI _p and Mo(VI) concentration in the range 2×10^–6 to 1.6×10^–5 M when using 3×10^–4 M 2-BIBH. Standard deviations of 5.6×10^–8 and 1.2×10^–8 M were found for 3×10^–6 and 8 × 10^–6 M Mo(VI), respectively.     

Cu(II)/Cd(II) coordination polymers based on polycarboxylate and 2-(2-pyridyl)benzimidazole

Three polycarboxylate coordination polymers containing 2-(2-pyridyl)benzimidazole as co-ligand, [Cu(Bdc)(2-PyBIm)] _n (1), [Cu(HBtc)(2-PyBIm)] _n (2) and [Cd₂(HBtc)₂(2-PyBIm)₂] _n ·; nH₂O (3) (H₂Bdc?=?1,4-benzenedicarboxylic acid; H₃Btc?=?1,3,5-benzenetricarboxylic acid), have been synthesized and characterized by elemental analyses, IR spectra, TG-DSC and X-ray structural analyses. Complex 1 is a one-dimensional zigzag chain in which the Cu(II) is cis six-coordinated by two chelating carboxyl groups and a 2-PyBIm ligand. Complex 2 is a two-dimensional (4, 4) network in which H₃Btc is partially deprotonated. Complex 3 has a three-dimensional framework in which one Cd(II) is six-coordinate and the other is seven-coordinate. All 2-PyBIm groups are neutral, chelating, bidentate ligands in 1–3. These complexes are quite thermally stable. The luminescence of 3 has also been investigated.     

Synthesis and Structure of an Unusual Carbonyl Ruthenium(II) Complex Containing Neutral NO2 as Ligand: [Ru(NO2)4(CO)(H2O)]Cl2·2H2O

A new ruthenium(II) complex [Ru(NO₂)₄(CO)(H₂O)]Cl₂ · 2H₂O has been prepared and characterized structurally. The compound crystallizes in monoclinic space group C2 /m, with the unit cell parameters a = 12.913(2), b = 14.605(2), c = 7.4494(1)Å, ß =121.49(2)°; V = 1198.0(3)ų, Z = 4, D_c = 2.429 Mgm^—3; μ = 1.83 mm^—1; R = 0.0455, wR = 0.1552. The complex contains four neutral NO₂ ligands. The ruthenium atom is six‐coordinated to four nitrogen atoms of nitrogen dioxide, one carbon atom from carbon monoxide and one oxygen atom from water molecule, forming slightly distorted octahedral coordination. The preparation procedure has been discussed.     

The rearrangement of 2-benzyl-5-mesitoyl-3(2H)-isothiazolone to 2-phenyl-6-mesitoyl-3,4-dihydro-1,3-thiazin-4(2H)-one

2-Benzyl-5-mesitoyl-3(2H)-isothiazolone ( 8 ) has been prepared from 3-mesitoylpropionic acid ( 5 ). Reaction of the isothiazolone 8 with sodium ethoxide in ethanol has been found to yield an isomeric rearranged compound, which was characterized as 2-phenyl-6-mesitoyl-3,4-dihydro-1,3-thiazin-4(2H)-one ( 9 ). This unexpected rearrangement is attributed to the abstraction of a benzylic hydrogen atom from the N-benzyl group, followed by ring enlargement through cleavage of the isothiazolone S? N bond.     

Reaktion von 3-(Dimethylamino)-2H-azirinen mit 1,3-Thiazolidin-2-thion

Reaction of 3-(Dimethylamino)-2H-azirines with 1,3-Thiazolidine-2-thione Reaction of 3-(dimethylamino)-2H-azirines 1 and 1,3-thiazolidine-2-thione ( 6 ) in MeCN at room temperature leads to a mixture of perhydroimidazo[4,3-b]thiazole-5-thiones 7 and N-[1-(4,5-dihydro-1,3-thiazol-2-yl)alkyl]-N′,N′-dimethylthioureas 8 (Scheme 2), whereas, in i-PrOH at ca. 60°, 8 is the only product (Scheme 4). It has been shown that, in polar solvents or under Me₂NH catalysis, the primarily formed 7 isomerizes to 8 (Scheme 4). The hydrolysis of 7 and 8 leads to the same 2-thiohydantoine 9 (Scheme 3 and 5). The structure of 7a, 8c , and 9b has been established by X-ray crystallography (Chapt. 4). Reaction mechanisms for the formation and the hydrolysis of 7 and 8 are suggested.     

Synthesis of sulphonated aminomethylphosphines and some nickel(II), palladium(II), platinum(II) and rhodium(I) complexes. Crystal structure of [Et3NH][(Ph2PCH2)2 N(CH2)2SO3]

Summary Aminoalkanesulphonic acids H₂N(CH₂) _n SO₃H, (n = 1, 2 or 3) react with phosphonium salts [R₂P(CH₂OH)₂]Cl (R = Ph or Cy, Cy = cyclohexyl) in the presence of Et₃N to give the sulphonated aminomethylphosphines [Et₃NH] [(R₂PCH₂)₂N(CH₂) _n SO₃] (R = Ph, n = 1, 2 or 3; R = Cy, n = 1). The single crystal X-ray structure of [Et₃NH] [(Ph₂PCH₂)₂N(CH₂)₂SO₃] has been determined. Some Ni^II, Pd^II, Pt^II and Rh^I complexes of the phosphines have been prepared.     

Synthesis and crystal structure of [Co(mpt)_2{P(OCH_3)_3}_2]BF_4 (Hmpt = 2-mercaptothiazoline)

The monomeric cobalt-phosphite-thiolato complex [ Co (mpt)2 {P (OCH3 )3 }2 ] BF4 (Hmpt = 2-mercaptothiazoline) has been prepared and characterized by X-ray crystallography. The complex crystallizes in the monoclinic space group C2/c with a= 0.8078(5), b=2.6020(18), c=1.2191(7) nm, β= 99.38 (1)°, V= 2.528(3) nm3, and Z = 4. The structure comprises discrete cations [Co(mpt)2{P(OCH3)3}2.] and anions BF4- , in which the cobalt (Ⅲ) atom is coordinated to two chelate mpt- and two as-oriented monodentate P(OCH3)3 ligands in a highly distorted octahedral geometry. The most distorted angles are S(2)-Co(1)-S(2a) of 162.23(10)° and N(1)-Co(1)-S(2) of 71. 47 (13)°, the latter is caused by the geometric constraint of the bidentate ligand mpt- . Cyclic voltammetry has been used to study the electrochemical behavior of the title complex on the R electrode in MeCN solution with 0.1 mol·L-1 of Bun4NBF4 as electrolyte. The results indicate that the title complex is unstable in MeCN.     

Copper(I)-anilide complex [Na(phen)3][Cu(NPh2)2]: an intermediate in the copper-catalyzed N-arylation of N-phenylaniline

Complex [Na(phen)₃][Cu(NPh₂)₂] ( 2 ), containing a linear bis(N‐phenylanilide)copper(I) anion and a distorted octahedral tris(1,10‐phenanthroline)sodium counter cation, has been isolated from the catalytic C? N cross‐coupling reaction with the CuI/phen/tBuONa (phen=1,10‐phenanthroline) catalytic system. Complex 2 can react with 4‐iodotoluene to produce 4‐methyl‐N,N‐diphenylaniline ( 3 a ) with 70.6 % yield. In addition, 2 can work as an effective catalyst for C? N coupling under the same reaction conditions, thus indicating that 2 is the intermediate of the catalytic system. Both [Cu(NPh₂)₂]^? and [Cu(NPh₂)I]^? have been observed by in situ electron ionization mass spectrometry (ESI‐MS) under catalytic reaction conditions, thus confirming that they are intermediates in the reaction. A catalytic cycle has been proposed based on these observations. The molecular structure of 2 has been determined by single‐crystal X‐ray diffraction analysis.     

Oxoanionic Noble Metal Compounds from Fuming Nitric Acid: The Palladium Examples Pd(NO3)2 and Pd(CH3SO3)2

The oxidation of elemental palladium at 100 °C in a mixture of fuming nitric acid and a pyridine‐SO₃ complex leads to the anhydrous nitrate Pd(NO₃)₂ (monoclinic, P2₁/n, Z=2, a=469.12(3) pm, b=593.89(3) pm, c=805.72(4) pm, β=105.989(3)°, V=215.79(2) ų). The Pd²⁺ ions are in square‐planar coordination with four monodentate nitrate groups which are connected to further palladium atoms, leading to a layer structure. The reaction of elemental palladium with a mixture of fuming nitric acid and methanesulfonic acid at 120 °C leads to single crystals of Pd(CH₃SO₃)₂ (monoclinic, P2₁/n, Z=2, a=480.44(1) pm, b=1085.53(3) pm, c=739.78(2) pm, β=102.785(1)°, V=376.254(17) ų). Also in this structure the Pd²⁺ ions are in square‐planar coordination with four monodentate anions; however, the connection to adjacent palladium atoms leads to a chain‐type structure. The thermal decomposition of the compounds has been investigated by means of DSC/TG measurements. Furthermore, IR and Raman spectra have been recorded, and an assignment of the observed vibrational frequencies has been carried out based on theoretical investigations.     

[2 + 2] cycloaddition of optically active ketenes. Synthesis of (−)-blastmycinone. Preliminary Communication

[2 + 2] Cycloaddition of (menthyloxy)methylketene ( 2 ) to cis-ethyl propenyl ether showed a ca. 3:1 diastereo-selectivity. A two-step transformation of the thermodynamically more stable adduct 4 furnished the (2R*, 3R*)-compound 5 with ca. 50% e.e. (Scheme 1). The analogous reaction sequence with cis- benzyl 1-hexenyl ether ( 9 ) and 2 showed a ca. 5:1 diastereoselectivity in 10 and 11 (Scheme 2). Absolute configuration of C(3) and C(4) in 11 has been proved by converting it to (?)-blastmycinone. Accordingly, the preferred transition state has been deduced as 15 .     

Characterization and Molecular Structure of Bis(Isopropyl Xanthate) Bis(1,10-Phenanthroline) Nickel(II): [Ni(phen)2(CH3)2CHOCSS](CH3)2CHOCSS

The crystal and molecular structure of the title compound, [Ni(phen)₂(CH₃)₂CHOCSS](CH₃)₂CHOCSS has been determined by X-ray diffraction. The brown crystal is triclinic of space group Pi, with parameters a = 11.790(2), b = 12.410(3), c = 12.680(3) Å, α = 92.49(3), β = 96.54(3), γ = 117.43(3)° and Z = 2. The compound contains a six-coordinate cation and an isopropyl xanthate anion (CH₃)₂CHOCSS^?, the central Ni atom is chelated by four nitrogen atoms of two phenanthroline ligands and two sulfur atoms of an isopropyl xanthate ligand. The TG data indicate that it decomposed completely at 734°C.     

Diamine complexes of nickel(II) nitrate: X-ray single crystal structural analysis of trans-[NiL2(NO3)2] [L = 1-(2-aminoethyl)piperidine]

Trans-[NiL₂(H₂O)₂](NO₃)₂ (pale blue) (1), trans-[NiL₂(NO₃)₂] (dark blue) (2), [L = 1-(2-aminoethyl)piperidine] and trans-[NiL₂ (H₂O)₂](NO₃)₂ (blue) (3) [L = 1-(2-aminoethyl)pyrrolidine] have been prepared. Complexes (1) and (3) upon heating undergo deaquation-anation yielding trans-[NiL₂(NO₃)₂] (dark blue) (2) and cis-[NiL₂(NO₃)](NO₃) (blue) (3a), respectively. The X-ray single crystal structure of complex (2) has been determined.     

Synthese und Strukturen von [ReNBr2(Me2PhP)3] und (Me2PhPH)[fac‐Re(NBBr3)Br3(Me2PhP)2]

Syntheses and Structures of [ReNBr₂(Me₂PhP)₃] and (Me₂PhPH)[ fac ‐Re(NBBr₃)Br₃(Me₂PhP)₂] [ReNBr₂(Me₂PhP)₃] ( 1 ) has been prepared by the reaction of [ReNCl₂(Me₂PhP)₃] with Me₃SiBr in dichloromethane. The bromo complex reacts with BBr₃ under formation of [Re(NBBr₃)Br₂(Me₂PhP)₃] ( 2 ) or (Me₂PhPH)[fac‐Re(NBBr₃)Br₃(Me₂PhP)₂] ( 3 ) depending on the experimental conditions. The formation of the nitrido bridge leads to a significant decrease of the structural trans influence of the nitrido ligand which is evident by the shortening of the Re‐(trans)Br bond from 2.795(1) Å in [ReNBr₂(Me₂PhP)₃] to 2.620(1) Å in [fac‐Re(NBBr₃)Br₃(Me₂PhP)₂]^– and 2.598(1) Å in [Re(NBBr₃)Br₂(Me₂PhP)₃], respectively.     

Crystal and molecular structure of organosilicon titanium(iv) derivatives: (Me3Si)3SiTi(NEt2)3 and ClTi[N(SiMe3)2]3

An X-ray structural study of two titanium-containing organosilicon compounds, (Me₃Si)₃SiTi(NEt₂)₃ (1) and ClTi[N(SiMe₃)₂]₃ (2), has been performed. The conformation of molecule1 in a crystal is staggered (approximate inherentC ₃ symmetry), the Ti-Si and Ti-N bond lengths are 2.671(2) and 1.874–1.890(5) Å, respectively. A crystal of1 consists of one type of enantiomers (the space group is P4₁2₁2; the absolute configuration has been determined). The structure of2 studied previously has been refined to the value of R=0.029 on the basis of 3442 reflections (the absolute structure has been determined), the Ti-Cl and Ti-N bond lengths are 2.260(1) and 1.926(1) Å, respectively. The strong distortions in the symmetry of the valence environment of the N atoms in the molecules of1, 2, and related structures are caused by electronic effects, in which the conformation of the relevant molecular fragments plays a determining role.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1473–1476, August, 1993.     

Synthetic and structural chemistry of nickel(II) complexes containing dithiolato and phosphine ligands I. Preparation and crystal structure of Ni2(PPh3)2(edt)2

A nickel(II) complex containing both dithiolato and phosphine ligands, Ni₂(PPh₃)₂(edt)₂ (edt = SCH₂CH₂S^2-), has been prepared and characterized by X-ray diffration. The complex crystallizes in the triclinic system, space group P-1, with a = 10.693(3), b = 17.457 (6), c = 10.606 (3) Å, α = 102.84(2), β = 96.49 (2), γ = 82.56(3); V = 1906.8 ų; D_c = 1.439 g·cm^?3 for Z = 2; the final conventional R was 0.052 based on 3338 observed reflections. Nickel atoms are linked by two sulfur atoms from two edt ligands with the Ni—Ni distance of 2.893 Å, and each Ni atom is coordinated by one phosphorus atom and three sulfur atoms with a square-planar geometry, where the average length of Ni—S bond is 2.180 Å and Ni—P bond 2.188 Å. The UV-Vis and ¹H NMR spectra have also been recorded.     

Preparation and characterization of a novel asymmetrically oxidized complex of 2-(diphenylphosphino)-benzenethiol with ruthenium. The crystal and molecular structure of [Ru(2-Ph2PC6H4S)·(2-Ph2PC6H4S−OH)(2-Ph2PC6H4SO2)]·1/2H2O

The reaction between [RuCl₂(PPh₃)₃] and 2-(diphenylphosphino)-benzenethiolate anion (DPPBT) yields the 18-electron Ru^II complex [Ru(DPPBT)₃][HNEt₃] (1), which is readily oxidised first to the neutral Ru^III complex [Ru(DPPBT)₃] (2), and then to the 18 electron Ru^III complex [Ru(2-Ph₂PC₆H₄S)(2-Ph₂PC₆H₄S−OH)·(2-Ph₂PC₆H₄SO₂)]·1/2H₂O (3). The x-ray crystal structure of complex (3) reveals it has a pseudo-octahedral geometry. One sulphur has been oxidised to a sulphinic acid (S−OH) group and a second to a sulphinate (SO₂) group, both being ligatedvia sulphur.     

[Cu(X-salicylato)2(N,N-diethylnicotinamide)2(H2O)2] complexes: conformational polymorphism and its consequence in supramolecular hydrogen-bonding networks formation

Novel copper(II) X-salicylate complexes with N,N-diethylnicotinamide (dena) of the formula [Cu(RCOO)₂(dena)₂(H₂O)₂] (RCOO = 3-methylsalicylate anion (3-Mesal, 1), 4-methylsalicylate anion (4-Mesal, 2), 5-methylsalicylate anion (5-Mesal, 3), 5-methoxysalicylate anion (5-MeOsal, 4) or 4-methoxysalicylate anion (4-MeOsal, 5)), and complex [Cu(3-MeOsal)₂(dena)₂(H₂O)₂]∙2H₂O (3-MeOsal = 3-methoxysalicylate anion (6)) have been prepared in the crystalline forms and characterized by spectroscopic methods (IR, Vis–UV, EPR). All the compounds according to their composition (1–5) seem to possess octahedral copper(II) stereochemistry. The complex 1 has been prepared in two different forms. X-ray analyses of the complexes 1, 4, and 5 were carried out and they featured a tetragonal-bipyramidal geometry around the copper atoms. The tetragonal planes are created by X-salicylate anions bonded to the copper(II) atoms via unidentate carboxylate oxygen atoms and the pyridine ring nitrogen atoms of the neutral ligand N,N-diethylnicotinamide, while in axial positions are water molecules. The two forms of complex 1 present conformation polymorphs and supramolecular isomers.     

Dielectric relaxations in a series of vinyl aromatic polymers: Poly(2-vinyl-N-ethylcarbazole), poly(3-vinyl-N-ethylcarbazole), poly(2-vinylanthracene), and poly(α-methyl-2-vinylanthracene)

Two dielectric relaxations have been studied on poly(2-vinyl-N-ethylcarbazole) (P2VK) and poly(3-vinyl-N-ethylcarbazole)(P3VK), poly(2-vinylanthracene) (P2VA) and poly(α-methyl-2-vinylanthracene) (PMe2VA). The relaxations in P2VK and P3VK occur in the temperature regions 220°C and ?150°C. Evidence for a third relaxation in both polymers at ca. 120°C has been found; and, for this reason, the relaxations studied (220°C and ?150°C) are labeled α and β, respectively, and have been attributed to T_g and carbazole rotational libration about the bond connecting the carbazole moiety to the polymer backbone. Additionally β (ca. 20°C) and γ(ca. ?150°C) relaxations in P2VA and MeP2VA have been observed and assigned, respectively, to wagging motion and rotational libration of the pendant anthracene moiety.