Volume 42, Issue 2

Syntheses of oxovanadium(V) thiolates such as O = V(SR) 3 (R = t C 4 H 9 , SiPh 3 ) and O=V(O t C 4 H 9 ) n (S t C 4 H 9 ) 3-n (n = 1, 2) are described. The thiovanadium(V) compounds S=V(O t C 4 H 9 ) 3 , S = V(S t C 4 H 9 )(O t C 4 H 9 ) 2 and S=V(SSiPh 3 ) 3 have been prepared by various methods :substition using Lawesson reagent, oxidation of V(O t C 4 H 9 ) 4 by sulfur, or disproportionation reaction of VCl 4 with LiSSiPh 3 ; O = V (OSiR 3 ) 3 (R = Me , Ph) undergoes a reaction with Lawesson reagent to yield dithiophosphonate complexes. All compounds obtained are characterized by 1 H and 51 V NMR spectroscopy; the stability of thiovanadium(V) compounds is discussed. V(S t C 4 H 9 ) 4 has been synthesized as a first example of vanadium(IV) thiolates

The title compound was prepared by reacting a corresponding mixture of Na 2 Te 2 , copper and tellurium at 700 °C. NaCu 3 Te 2 forms crystals of metallic lustre which are rapidly decomposed in humid atmosphere. It crystallizes with a rhombohedral structure, space group R3m, with a = 4.276(3) Å, c = 23.78(1) Å, Z = 3. The crystal structure was determined from diffractometer data and refined to a conventional R of 0.050 for 135 independent reflections. The atomic arrangement of NaCu 3 Te 2 is based on a c.c.p. array of tellurium atoms with stacking sequence c 6 . Na and Cu occupy alternatingly the interstitial layers. Na is in an octahedral coordination (d̄ Na-Te : 3.22 Å), the Cu atoms occupy the tetrahedral and the octahedral voids. They are, however, shifted from the centers of these sites, resulting in an 1 + 3 coordination (d̄ Cu-Te : 2.70 Å) for Cu on the tetrahedral. and an essentially trigonal coordination (d Cu-Te : 2.575 Å) for Cu on the octahedral sites. NaCu 3 Te 2 shows no closer structural relationships to the other alkali-copper-chalcogenides known so far. However, its crystal structure may be interpreted as an ordered defect derivative structure of the CaCu 4 P 2 -type [1].

KCrF 4 has been prepared as yellowish-green single crystals (by heating of KF, CuF 2 , CrF 3 ; Au-tube, 750 °C, 60d). It crystallizes in the orthorhombic crystal system (Pnma) with: a = 1573.2, b = 743.2, c = 1833.1 pm, Z = 24. The structure shows [Cr 3 F 9 F 6/2 ] 3- -columns along [010], The Madelung Part of Lattice Energie, MAPLE, is calculated and discussed, along with Effective Coordination Numbers, ECoN (via Mean Fictive Ionic Radii, MEFIR). The structure is described using SCHLEGEL-diagrams.

trans-1,2-Dichloro-1,2-bis(trichlorosilyl)ethene (1) was prepared from Cl 3 CSiCl 3 and copper powder, and its structure determined by single crystal X-ray diffraction (monoclinic, space group P2 1 /n, a = 7.297(1), b = 10.964(1), c = 7.988(1) Å, β = 108.06(1)°; R = 0.037, R w = 0.066). Cl 3 SiC=CSiCl 3 , 2, forms a cobalt cage cluster on reaction with Co 2 (CO) 8 formulated as (CO) 6 Co 2 C 2 (SiCl 3 ) 2 . Hydrosilylation with HSiCl 3 gives tris(trichlorosilyl)ethene. -Bis(trimethylsilyl)ethine adds HSiCl 3 to form 1-trichlorosilyl-1,2-bis(trimethylsilyl)ethene, which can be converted into the hydride with i-BU 2 AlH. All compounds are model systems for CVD production of amorphous silicon a-Si:C.

The title complex has been prepared from Ga[GaBr 4 ] and [2](1,4)naphthalino[2]paracyclophane in toluene as a solvent, and the crystal structure of this adduct determined by single crystal X-ray diffraction. The structure is composed of dimeric units Ga 2 [GaBr 4 ] 2 , which are crosslinked into sheets through Ga(I)-arene coordination. Both the benzene ring and the substituted ring of the naphthalene system are η 6 -bonded from the outer side of the cyclophane cage, each to an univalent metal. The benzene and the naphthalene form an interplane angle of 49.3°. The distance to the benzene ring (2.67 Å) is much shorter than the distance to the naphthalene (2.85 Å), suggesting a stronger complexation with the unperturbed π-system of the former. [2.2](l,4)Naphthalinophane forms no adduct with Ga[GaBr 4 ], and with [2](l,5)naphthalino[2]paracyclophane secondary reactions are observed.

The two title compounds have been prepared by reaction of appropriate mixtures of the elements in ethylenediamine. The structures have been determined on the basis of single crystal data. [Ba(en) 3 ]Te 3 crystallizes in the monoclinic system, space group P2 1 /c with a = 918.0(4), b = 1203.7(6), c = 1639.9(6) pm, β = 93.4(1)°. In the structure there are bent tritelluride anions Te 3 2- (bond lengths 273.9-278.5 pm, bond angle 105.7°). The Ba 2+ cations are six coordinate by the bidentate ligand ethylenediamine. [Ba(en) 4,5 ]Te 3 crystallizes in the monoclinic system, space group Cc with a = 1752.8(6), b = 938.9(4), c = 3041.7(8) pm, β = 91.3(1)°. In this structure the bond lengths in the Te 3 2- anions are shorter (272.1-273.1 pm, bond angles 110.9-112.2°). The cations are coordinated by four bidentate ligands, and are connected into pairs by a further ethylenediamine molecule. The resulting dinuclear [Ba(en) 4 ]en[Ba(en) 4 ] 4+ units have the Ba 2+ cations in CN 9.

Under hydrothermal conditions aqueous solutions of copper(II) sulfate (1) are reduced by means of saturated fatty acids with hydrogen at the α-atom to yield crystalline copper. In all cases carbon dioxide is liberated and lower fatty acids and ketones can be identified as reaction products. α-Hydroxy and α-aminocarboxylic acids proved to be very effective reducing agents towards 1. The yield of copper varied from 2 to 2.5 mol Cu per 1 mol of amino acid. The reaction of 1 is suppressed by sulfuric acid. The presence of hydrochlorid acid or chlorides leads to the precipitation of copper(I) chloride. The mechanisms of the decomposition of the various types of carboxylic acids is discussed. It was also possible to precipitate metallic copper by means of various proteins.

The Raman spectrum of commercial "sulfur dichloride" shows strong lines due to SCl 2 and S 2 Cl 2 and weak Cl 2 lines at 25 °C, but strong SCl 2 and SCl 4 signals at -100 °C (the latter are superimposed on the S 2 Cl 2 lines). Thus, the intense Raman effect of SCl 4 can be used to detect small amounts of chlorine in SCl 2 . Mixtures of SCl 2 and Cl 2 (1:15) yield the Raman spectrum of SCl 4 at -140 °C, while at 25 °C not trace of this compound can be detected. The spectra of SCl 4 and α-SeCl 4 are quite different, indicating different molecular and/or crystal structures, although ECl 3 + ions (E = S, Se) are present in both cases. While Se 2 Cl 2 dimerizes reversibly below -50 °C, S 2 Cl 2 neither dimerizes nor isomerizes on cooling. The S 2 Cl 2 dimer is characterized by a Raman line at 215 cm -1 the intensity of which was used to calculate an enthalpy of dimerization as of -17 kJ/mol.

By addition of solutions of nitrosyl hexachloroantimonate(V) in acetonitrile or of diiodine in n-hexane to a solution of 2.3.7.8-tetramethoxythianthrene (“Vn 2 S 2 ”, 1) in toluene the oxidation products [Vn 2 S 2 ][SbCl 6 ] • CH 3 CN (2) and [Vn 2 S 2 ]I 3 (3), resp., are formed. Crystal structure determinations show both compounds to contain the [Vn 2 S 2 ] + ion. In contrast to the folded parent compound Vn 2 S 2 its monocation [Vn 2 S 2 ] T is planar, the short CS and CO distances (172-173 pm and 134-135 pm resp.) indicate an extended mesomeric system. Both compounds crystallize with segregated stacks of cations and anions. In 2 the coplanarly and equidistantly stacked [Vn 2 S 2 ] + ions have an A,B-sequence (distance between the planes of the ions 353 pm, intermolecular S···S distance 366 pm). In 3 the [Vn 2 S 2 ] + ions form dimers by SS contacts (S···S distance 316 pm); these dimers are arranged in a stair-like manner (distances between atoms of adjacent dimers 350-380 pm). The conductivities of 2 and 3 are 9.4 • 10 -9 and 5.3 • 10 -6 Sem -1 , resp.

Starting with the secondary phosphanes R 2 PH (R = Me, Ph, iPr) and the vinyl-or allylmethylphosphinic acid isopropylesters, the triphosphaalkanes R 2 P-[CH 2 ] 3 -PMe -[CH 2 ] 2 -PMeH containing one terminal PH-group have been synthesized in a multiple step synthesis. The tertiary-secondary phosphanes R 2 P-[CH 2 ] 3 -PMeH obtained as intermediates may be used for the syntheses of hybrid donor systems PPN. The P-C-skeletons of the tetra-and pentadentate oligophosphaalkanes have been built up by a free radical initiated addition of the vinyl or allyl compounds CH 2 =CH-P(NEt 2 ) 2 or CH 2 =CH-CH 2 -P(O)(OiPr)Me to disecondary or disecondary-tertiary phosphanes, HMeP-[CH 2 ] n -PMeH (n = 2, 3) or HMeP-[CH 2 ] 3 -PPh-[CH 2 ] 3 -PMeH, respectively. Methanolysis of the tetra-and pentaphosphaalkanes with terminal P-NEt 2 functional groups affords the methoxy derivatives in almost quantitative yield. While the terminal P(NEt 2 ) 2 groups in the oligophosphaalkanes cannot be reduced by LiAlH 4 , the corresponding methoxy derivatives react immediately to give the primary-tertiary phosphanes.

The reactions between 2,3-dihydro-1,3-diborole derivatives 1 and potassium in tetrahydrofuran yield dark brown solutions. Without elimination of hydrogen, 1.4 to 1.8 moles of potassium are consumed by one mole of 1. Reduced 1 and iodomethane react to give methylated products, identified by GC/MS studies. Complexation with (C 5 H 5 )Co(C 2 H 4 ) 2 leads to the cyclopentadienyl-cobalt complexes 2, iso-2, 3, and 4, of which iso-2 is a new cobalt-hydride sandwich. Methylation reactions of the cobalt sandwich anions (2-H) - are reported.

Atropisomerism owing to hindered rotation about the N-aryl bond is observed in 4,5-diethyl-2,2,3-trimethyl-1-(o-trifluormethyl)phenyl-2,5-dihydro-1H-1,2,5-azasila-(2) and -azastanna-boroles (5). The compounds 2 and 5 are characterized by elemental analysis, mass spectra and 1 H, 11 B, 13 C, 29 Si and 119 Sn NMR. The ortho-trifluoromethyl group serves as an additional NMR spectroscopic probe because of “through space” 19 F- 1 H and 19 F- 13 C spin spin coupling. Compound 5 is the first derivative of a 2,5-dihydro-1H-1,2,5-azastannaborol.

The reaction of 8-aza-and 7-deaza-8-aza-purines with Cu 2+ cations in acid solution has been studied. At a pH value of 2, the 8-azaadenine complex [Cu(H 2 O) 4 (AAdH) 2 ](NO 3 ) 2 (1), which displays Cu-N9 coordination, may be isolated from solution. The reaction of CuCl 2 with 8-aza-hypoxanthine in concentrated HCl solution leads to ring opening at C2 of the azapurine with subsequent formation of dichlorobis[(5-amino-4-carboxamide)[1 - 3]triazole] copper(II) dihydrate 2, in which the triazole ligands display a chelating function, coordinating the metal via N7 and O6. The results for 1 and 2 suggest that copper coordination of the azapurine base is not a prerequisite for opening of the pyrimidine ring. Respectively N9-and N8-coordinated complexes [CUCl 3 (AllH 3 )] n 3 and [CuCl 2 (H 2 O)(MAllH)] n (4) of allopurinol (AllH 2 ) and 9-methylallopurinol (MAllH) may be prepared by the reaction of CuCl 2 with the respective bases in HCl solution. In contrast, with the analogous 1-methyl-4-aminopyrazolo[3,4-d]pyrimidine MAPP, only the salt (MAPPH) 4 (CU 2 Cl 8 ) (5) could be isolated under similar conditions, indicating that N8 is less attractive as a binding site in this 7-deaza-8-azaadenine derivative. The structures of 1-5 have been established by X-ray structural analysis. A distorted octahedral [4+2]geometry is found for the copper atoms in 1 and 2. Chlorine bridged polymeric chain structures are adopted by the complexes 3 and 4. An intermediate coordination geometry between trigonal bipyramidal and square-pyramidal is observed for the metal atoms in 3, a distorted square-pyramidal geometry in 4.

Phosphonomanganese complexes (CH 3 O) 2 (O)PMn(CO) 3 [P(OCH 3 ) 3 ] 2 (1b), (CH 3 O) 2 (O)PMn(CO) 2 [P(OCH 3 ) 3 ] 3 (1c) are obtained via demethylation of the corresponding cationic substituted carbonylmanganese compounds with KHB(secBu) 3 . The reaction of NaBH 4 in methanol with cationic phosphorus donor substituted carbonyl manganese compounds leads to formyl complexes (OC) 3 L 2 MnCHO (L = P(OCH 3 ) 3 (3a), L = P(OEt) 3 (3c), L = P(OiPr) 3 (3d), L = PPh 3 (3e)) and (OC) 2 [P(OCH 3 ) 3 ] 3 MnCHO (3b). 3d decomposes thermally to give an (OC) 3 [P(OiPr) 3 ] 2 MnH and an (OC) 2 [P(OiPr) 3 ] 3 MnH complex. The latter has been characterized by an X-ray structure determination.

(Diazomethyl)diphenylphosphine oxide (2a) adds onto the 1-cyclopropene phosphonates 1a and c under formation of the 2.3-diazabicyclo[3.1.0]hex-2-enes 3a and c. 3a is easily converted into the 1.4-dihydropyridazine 5a. On the other hand the reaction of 1b with 2a directly affords the 1.4-dihydropyridazine 5b. The 2.3-diazabicyclo[3.1.0]hex-2-enes 3a and c isomerize to the allyl diazomethanes 4a and c on heating in benzene. In the case of the reactions 2b+1b as well as 6+1a the direct formation of allyl diazo compounds (4d and 8a respectively) is observed. In a novel reaction 9-diazofluorene (6) yields the 1.3-butadiene 9 when reacted with the cyclo-propene 1b.

Alkylation of 1,5-benzothiazepin-4(5H)-one (1) with dimethyl sulfate and base yields the N-methyl compound 2 whereas with trimethyloxonium fluoroborate the lactimether 3, a simple derivative of the unknown, 1,4-thiazepine is obtained. Compound 3 eliminates sulfur on heating in toluene, yielding 2-methoxy-quinoline. Oxidation of 3 with peracid produces the stable 1,1- dioxide (4).

Two isomers of 7-methyl-9-oxo-2,4-diphenyl-3-oxa-7-aza-bicyclo[3.3.1]nonan-1,5-ethyl dicarboxylate (1a and 1b) were obtained by condensation of 2,6-diphenyl-1-oxa-4-oxo-cyclohexan-3,5-ethyl dicarboxylate with methylamine and formaldehyde. Their crystal structures were determined by X-ray diffraction. They crystallize in the triclinic space group P1̄ with (for 1a) a = 12.907(5), b = 11.223(4), c = 8.993(4) Å, α = 105.82(4), β = 100.14(5), γ = 97.35(4)°, and (for 1b) a = 16.400(7), b = 13.062(4), c = 11.336(2) Å, α = 94.19(3), β = 94.74(3), γ = 102.56(4)°. This investigation has shown that isomer 1a has the boat-chair conformation, and isomer 1b has the chair-chair conformation. The formation of la causes a configurational change of the phenyl substituents. The two species are characterized by NMR spectroscopy. - Another comparable bicyclononanone with a bulky substituent at the nitrogen atom has been synthesized and was investigated spectroscopically. This compound should have chair-boat conformation (with the boat conformation in the N-heterocyclic ring) whereas 1a has the boat conformation in the O-heterocyclic ring.

Sarcosinanhydride-monolactamacetal (7) furnishes an equilibrium concentration of the electronically activated tetrahydropyrazine 3b which yields in contrast to other pyrazine derivatives with 4-nitrophenylazide (4) the cycloaddition product 9. Catalytic cleavage of 9 leads to the triazene compound 11.

The following mixed ligand complexes were synthesized and characterized: Co(Phdtcz) 2 (Phtu) 2 , Co(Phdtcz) 2 (Clphtu) 2 , Co(Phdtcz) 2 (dtm), Ni(Et 2 dtc) 2 (dtm), Ni(Phdtc) 2 (dtm), Ni(p-Toluiddtc) 2 (dtm), Ni(α-naphdtc) 2 (dtm), and Ni(Phdtcz)(Et 2 dtc); where Phdtcz = phenyldithiocarbazate, Et 2 dtc = diethyldithiocarbamate, Phdtc = phenyldithiocarbamate, p-Toluiddtc = p-toluidinedithiocarbamate, α-naphdtc = α-naphthyldithiocarbamate, Phtu = phenylthiourea, Clphtu - chlorophenylthiourea, and dtm - bis(diphenylphosphinothioyl)-methane. Electronic and IR spectra, magnetic, conductivity and X-ray powder diffraction measurements were carried out. The Ni(II) and Co(II) complexes are suggested to be square planar and octahedral, respectively. The biological activity of the complexes was also tested.

Bromination of N-(4-oxopentyl)phthalimide (3) leads to isomeric bromoketones 2a and 2e, which undergo cyclisation with formamidine in liquid ammonia to yield homohistamine (1a) and 5-methylhistamine (1e). Similarly racemic a-methyl-(1b) and 2-methylhomohistamine (1c) are synthesized. The resolution of 1b is achieved using (+)-and (-)-di-0-(4-toluoyl)tartaric acid. 1 are intermediates in the synthesis of impromidine like, H 2 -histaminergic compounds.

The conversion of euphorianin to deacetyldehydroeuphorianin which was used in an X-ray crystal structure analysis is described. A new pentacyclic structure related to ingol tetraacetate is described for euphorianin.

The crystal structures of LiGaCl 4 and LiGaI 4 have been determined by single crystal X-ray methods. Both compounds are isotypic with LiAlCl 4 and characterized by LiX 6 octahedra and GaX 4 tetrahedra. Mean bond lengths are: d̄(Ga-X) = 217.4 pm (Cl) and 255.9 pm (I); d̄(Li-X) = 263.9 pm (Cl) and 305.3 pm (I), respectively. Common features of the isotypic compounds LiGaX 4 (X = Cl, Br. I) are discussed.

The crystal structure of In I ln III Br 4 (Indium-Di-bromide) has been determined by single crystal methods. The compound crystallizes with a GaCl 2 -type arrangement in the orthorhombic space group Pnna with the lattice constants: a = 797.6(2) pm, b = 1036.6(2) pm, c =1038.8(2) pm.

Acetylene complexes of tungsten(IV) of the type [WCl 4 (RC≡CR)]2 (R = halogene, phenyl) react with tetrachloro-1,2-benzoquinone to give monomeric tungsten(VI) chelate complexes WCl 2 (O 2 C 6 Cl 4 ) 2 and W(O 2 C 6 Cl 4 ) 3 , respectively. The complexes have been characterized by their IR and mass spectra.