Volume 52, Issue 1

Bis[bis(dimethylamino)phosphino]acetylene (2a) and two molecules of dimethyl- and diethyl-acetylenedicarboxylate (1a /1b ) react in a criss-cross-cycloaddition to yield 1λ 5 ,4λ 5 - diphosphapentalenes (3), which react further with 1 to yield a 1λ 5 ,4λ 5 -diphosphaazulenes (5). A mechanism of both reactions is proposed. The reaction of 1λ 5 ,4λ 5 -diphosphaazulene with 1a at high pressure yields 1,1,4,4-tetrakis(dimethylamino)-3,5,6,7,8 -pentakis(methoxycarbonyl)- 2-[1,2,2tris(methoxycarbonyl)ethenyl]-1λ 5 ,4λ 5 -diphosphaazulene (7). The reaction of bis(diphenylphosphino) acetylene (2c) with 1a yields 1,5a-dihydro-1-methoxy-(1-methoxycarbonylethinyl)- 3,3,7,7-tetraphenyl)-2-oxa-3λ 5 ,7λ 5 -diphosphacyclopenta[1,2,3-c,d]azulene- 4,5,5a,6,8,9-hexakis(methoxycarbonyl) (9) and 4-(diphenylphosphoryl)-5-[1,2-bis-(methoxycarbonyl)- ethylidene]-1λ 5 -phosphol-2,3-bis(methoxycarbonyl) (10)

Ph 3 SnCH 2 CH 2 CH(NHCOOCH 2 Ph)COOCH 3 (1) is synthesized by hydrostannation of methyl N-(benzyloxycarbonyl)vinylglycinate with Ph 3 SnH. The reaction of 1 with HCl in CH 3 OH and with bromine in CHCl 13 yields the halostannylsubstituted compounds Ph 3-n X n SnCH 2 CH 2 CH(NHCOOCH 2 Ph)COOCH 3 (2 - 4) (n = 1, 2; X = Cl, Br). By saponification with one equivalent of NaOH and subsequent acidification with HCl 1 is transformed into the free acid Ph 3 SnCH 2 CH 2 CH(NHCOOCH 2 Ph)COOH (5) that undergoes cyclization into the 1,2-oxastanninane 6 with intramolecular elimination of benzene. IR, NMR data and the determination of the crystal structure of Ph 2 BrSnCH 2 CH 2 CH(NHCOOCH 2 Ph)COOCH 3 (3) reveal for 2 and 3 an intramolecular coordination of the NC(O)O-group at the tin atom to form a seven-membered ring

The rac-lipoato (lip - ) complexes [Zn(lip) 2 (H 2 O) 2 ] (1) and [Cd(lip) 2 (H 2 O) 2 ] (2) were obtained in good yields from solutions of sodium lipoate and the respective metal nitrate in methanol/water. 1 and 2 form pale yellow, moderately light-sensitive crystals. Both compounds were structurally characterized by single-crystal X-ray diffraction. 1: C2/c, a = 39.958(6), b = 5.360(1), c = 10.794(1) Å, β = 95.76(1)°, Z = 4, wR2 = 0.150 (all data). 2: C2/c, a = 38.200(2), b = 5.472(1), c = 11.179(1) Å, β = 92.72(1)°, Z = 4, wR2 = 0.090 (all data). The metal ions are hexacoordinated by the oxygen atoms of two chelating carboxylate ligands and two aqua ligands. The crystal structures are very similar but not isotypic. They are layer structures, in which the complexes within a layer are interconnected by a network of hydrogen bonds. Adjacent layers have contacts via the 1,2-dithiolanyl rings of their lipoato ligands. Crystals of 1 and 2 decompose on exposure to visible light or ultraviolet radiation in the 280-390 nm range. Photopolymerization by formation of intermolecular S-S bonds is very probably involved. Furthermore, the infrared spectra reveal the transformation of COO - into COOH groups

By photochemically induced oxidative addition reactions the synthesis of some new tinorganic compounds was achieved. The reaction of dichloro-and diiodotin with 1,2-diiodobenzene (1) induced by ultraviolet radiation led to bis-(1-iodophenyl)diiodotin (2), bis-(1-iodophenyl)dichlorotin (3), 1 -iodo-2-(trichlorotin)benzene (4) and 1-iodo-2-(triiodotin)benzene (5). Iodosubstitution at the tin atom was also observed when dichlorotin was used as the starting compound. Analogous experiments with 1,2-dibromobenzene (6) and 1,2-dichloro-(7) gave no products

Reaction of allyltribromogermane (2), readily available from dibromo(1,4-dioxane)germanium(II) (1) and allylbromide, with tris(2-tributylstannoxyethyl)-amine (4) gives 1-allylgermatrane (3) in almost quantitative yield. 3 crystallizes from n-pentane as a colourless crystalline solid which was characterized by 1 H and 13 C NMR spectroscopy and by an X-ray crystal structure study. The “atrane” skeleton shows a strong conformational disorder; the Ge-N distance of 2.208(3) Å suggests the presence of a coordinative Ge-N bond. Treatment of 1-allylgermatrane (3) with CH 2 N 2 in the presence of catalytic amounts of Pd(OAc) 2 affords 1-cyclopropylmethylgermatrane (5) in high yield

Pb 3 Fe 2 Te 2 O 12 (I) and Pb 2 CoTeO 6 (II) have been prepared by crystallization from melts. Single crystal X-ray investigations led to monoclinic (I) and tetragonal (II) symmetry, space groups C 4 s -Cc and D 17 4h -14/mmm. Lattice constants I: a = 9.866(3), b = 15.332(4), c = 7.172(2) Å, β = 111.34(3)°, Z = 4. II: a = 5.661(5), c = 8.004(7) Å, Z = 2. (I) represents a new crystal structure, characterized by a network of octahedra occupied by Fe 3+ and Te 6+ in a disordered manner. The centres of negative charge of the lone pairs of Pb 2+ in I are estimated by Coulomb term calculations. II belongs to the elpasolithe type

1-Butyl-2,3,4,5-tetraphenyl-2,4-cyclopentadiene (3) is prepared starting from 2,3,4,5-tetra-phenylcyclopentadien-1-one which forms 1-butyl-1-hydroxy-2,3,4,5-tetraphenylcyclopentadiene (1) by reaction with BuLi followed by acid hydrolysis. 1 and HBr give 1-bromo-1-butyl-2,3,4,5-tetraphenylcyclopentadiene (2), which in its turn reacts with BuLi and H 2 O /H + to yield 3. Treatment of 3 with NaNH 2 , TlOEt or FeCl 2 yields Na[C 5 Ph 4 Bu] (4), Tl[C 5 Ph 4 Bu] (5) and the corresponding ferrocene Fe[C 5 Ph 4 Bu] 2 (6), respectively. The 1 H and 13 C NMR spectra of the new compounds are reported and discussed

1,4-Diphenyl-1,3-cyclopentadiene reacts with acyl chlorides RC(O)Cl (R = CH 3 (a), C 5 H 11 (c )) to form the corresponding 1,4-bis(4-acylphen-1-yl)-1,3-cyclopentadienes C 5 H 4 (C 6 H 4 C(O)R) 2 (1a, 1c), which upon treatment with NaNH 2 or with TlOC 2 H 5 afford the corresponding sodium complexes Na[C 5 H 3 (C 6 H 4 C(O)R) 2 ] (2a, 2c) or thallium(I) derivatives Tl[C 5 H 3 (C 6 H 4 C(O)R) 2 ] (3a, 3c). The reaction of 1,1′,3,3′-tetraphenylferrocene with CH 3 C(O)Cl results in the formation of Fe[C 5 H 2 {C(O)CH 3 } {(C 6 H 4 C(O)CH 3 ) 2 }]- [C 5 H 3 {(C 6 H 4 C(O)CH 3 ) 2 }] (5), whereas 2c and FeCl 2 give Fe[C 5 H 3 (C 6 H 4 C(O)C 5 H 11 ) 2 ] 2 (4c). The all-para-acylated tetraphenylcyclopentadienes C 5 H 2 (C 6 H 4 C(O)R) 4 (R = CH 3 (a), C 3 H 7 (b)) react with K[N 2 H 4 OH] to produce the ligands C 5 H 2 (C 6 H 4 CH 2 R) 4 (6a, 6b), which undergo reactions with NaNH 2 and TlOC 2 H 5 to yield the sodium and thallium(I) salts, Na[C 5 H 2 (C 6 H 4 CH 2 R) 4 ] (7a, 7b) and Tl[C 5 H 2 (C 6 H 4 CH 2 R) 4 ] (8a, 8b), respectively. 7a and 7b react with FeCl 2 to produce the corresponding ferrocenes Fe[C 5 H(C 6 H 4 CH 2 R) 4 ] 2 (9a, 9b). The 1 H and 13 C NMR spectra of the new compounds are reported and discussed

The reaction of (MeNC)-, (PhNC)- and (MesNC)AuCl in tetrahydrofuran with an equimolar amount of the corresponding isonitrile ligand and one equivalent of Ag + X - (X - = BF - 4 or CF 3 SO - 3 ) leads to the formation of the bis(isonitrile)gold(I) complexes (MeNC) 2 Au + CF 3 SO - 3 (1), (PhNC) 2 Au + BF - 4 (2) and (MesNC) 2 Au + BF - 4 (3). The crystal structures of 1, 2 and 3 have been determined. In compound 1 there are rod-like cations with a parallel packing into meandering puckered layers, in which the gold atoms have alternating Au-Au contacts of 3.611 and 3.624 Å. In complex 2 the cations form long double-paddles, with the two paddles at an angle of 77.5°. The individual cations are well separated and have no sub-van-der-Waals Au-Au contacts. The crystal structure of 3 is similar, but with a smaller dihedral angle between the planes of the two mesityl rings (56.0°)

By reaction of [B 6 H 7 ] - with PhHg(CH 3 COO) in dichloromethane [Hg(η 3 -B 6 H 6 )Ph] - is formed. The crystal structure of [PPh 4 ][Hg(η 3 -B 6 H 6 )Ph] has been determined by single crystal X-ray diffraction analysis; monoclinic space group P 2 1 /c with a = 9.567(5) Å, b = 22.213(5) Å, c = 14.296(5) Å, β = 94.484(5)°. The 11 B NMR spectrum exhibits a doublet at -9.9 ppm shifted to lower field as compared with [B 6 H 7 ] - and the 199 Hg NMR spectrum a singlet at -74.5 ppm. In the IR and Raman spectra characteristic B-H vibrations are observed

Ligand exchange reactions of tetrachloro-bis(triphenylphosphane)rhenium(IV) with sali-cylaldehyde-2-hydroxy(mercapto)anil were studied. The reaction products were characterized by mass spectroscopy. The crystal structure was determined by X-ray analysis for bis[sali-cylaldehyd-2-hydroxyanilato(2-)]rhenium(IV). Crystal data: a = 1987.1(18); b = 829.0(6), c = 1296.9(7) pm, β = 100.02(7)° ; space group C 2/c; Z = 4

The dication of tetrakis(dimethylamino)ethene (TDAE 2+ ) forms ion pair complexes with [M(mnt) 2 ] 2- , mnt 2- = maleonitrile-2,3-dithiolate, M(II) = Ni, Pd, Pt, and Zn. According to X-ray analysis the structure of {TDAE 2+ [Pt(mnt) 2 ] 2- } consists of a chain-like arrangement of planar dianions and twisted (71°) dications. Shortest interionic contacts are 11 pm longer than the corresponding van der Waals radii. In the UV-VIS diffuse reflectance spectra of the complexes with a d 8 central metal there is no unambiguous evidence for the presence of an ion pair CT band. This band is observed, however, at 450 nm when the d 10 metal Zn(II) is present. Application of the Hush-Marcus model affords a reorganization energy of 110 kJ / mol for electron transfer from [Zn(mnt) 2 ] 2- to TDAE 2+ . This value is 40 kJ / mol higher than the one reported for the analogous complex wherein TDAE 2+ is replaced by a 2,2′-bipyridinium acceptor of similar reduction potential

The solid-state structures of the low-melting compounds bis(trifluoromethyl)disulfane (CF 3 SSCF 3 , triclinic, space group P 1̄, Z = 2) and bis(trifluoromethyl)trisulfane (CF 3 SSSCF 3 , monoclinic, space group C2/c, Z = 4) have been determined on single crystals with MoK α radiation at -160°C. The trisulfane has trans conformation. The geometry of both molecules agrees well with results of electron diffraction on the gaseous state. A comparison is made also with the crystal structures of the related molecules CF 3 TeTeCF 3 and CF 3 OOOCF 3

The applicability of ketals was examined for masking the carbonyl group in N-tertiary 4-piperidones during the dehydrogenation using mercury-edta. Various 1,3-dioxolanes showed a different behaviour in dependence on the N-substituent. With simple aliphatic moieties mainly dehydrogenated but hydrolyzed products were received. These enaminones were also available from the dehydrogenations of the corresponding 4-piperidones. Similar applied to para-acyl-aromatic substituted derivatives but with less yields. Aromatic substituents bearing a neighbour group on ortho-position with participation gave rise to different oxidation products partially with preservation of the ketal structure

The dinuclear metallacycle of [Cp′ 2 Ti(μ-S 2 ) 2 TiCp′ 2 .] reacts with phosgene or thiophosgene to give [(Cp′ 2 CITi) 2 S 3 ] which has been characterized by 1 H and 13 C NMR spectra as well as by an X-ray structure analysis. The trisulfido complex contains a helical TiSSSTi unit and may serve as an S 3 transfer reagent in reactions with SCl-functional compounds

A new alkaline earth vanadyl arsenate Ba(VO) 4 (AsO 4 ) 2 (As 2 O 7 ) has been synthesized by solid state reactions in closed quartz tubes. X-ray investigations led to orthorhombic symmetry, space group D 16 2h -Pnma, α = 17.540(2), b = 7.6223(8), c = 11.0633(12) Å, Z = 4. The crystal structure is characterized by AsO 4 single and As 2 O 7 double tetrahedra and face shared asymmetric stretched V 2 O 8+1 , double octahedra, forming a network of polyhedra. The incorporated Ba 2+ ions show 12-fold coordination by oxygen. Ba(VO) 4 (AsO 4 ) 2 (As 2 O 7 ) is the first vanadyl compound containing V 2 O 8 divanadyl groups originating from face sharing stretched VO 5+1 octahedra

The crystal structure of CH 3 C 6 H 4 S(O) 2 NCl 2 is reported. Crystals are monoclinic, space group P2 1 /c, with a = 710.0(7), b = 1615.3(13), c = 867.2(7) pm, V = 988(2) pm 3 and Z = 4. The reaction with HF/SbF 5 yields CH 3 C 6 H 4 S(O) 2 NCl 2 H + SbF - 6 the first protonated dichloroamine salt, its vibrational -and NMR spectra are discussed

The following compounds have been prepared and characterized by crystal structure analyses: Two modifications of bis[μ-nitrido-bis(diphenylphosphinato-O,O′)]boronium (1+) triiodide (A and B): A (monoclinic, P2 1 /c; a = 1908.8, b = 1652.7, and c = 1719.4 pm; β = 109.54°; Z = 4; = 10.3%) and B (triclinic, P 1̄, a = 981.8, b = 1148.9, and c = 2353.7 pm; α = 80,91°, β = 81.09°, γ = 74.58°, Z = 2, wR = 7.4%). Tris[μ-nitrido-bis(diphenylphosphinato-O,O′)]aluminium( 1 +) triiodide (C) and tris[μ-imidobis(diphenylphosphinato-O,O′)]aluminium (1+)bis(hydrogenphosphate) dioxane adduct (D): C (monoclinic, P2 1 /n ,a = 1332.4, b = 4087.6, an d c = 1368.1 pm; β = 93.17°; Z = 4; R = 10.4%) and D (orthorhombic, Pc2 1 b, a = 1798.7, b = 2151.1, and c = 1948.7 pm; Z = 4; R = 12,8%). Two modifications of tris[μ-nitrido-bis(diphenylphosphinato-O,O′)]stannium (1+) perchlorate (E and F): E (triclinic, P 1̄, a = 1468.7, b = 1480.2, and c = 1629.8 pm; α = 99.75°, β = 90.77°, and γ = 92,65°, Z = 2, wR = 6,0%) and F (hexagonal, a = 1224 and c = 2110 pm). Bis[μ-nitridobis(diethylphosphinato-O,O′)]boronium (1+) triiodide has been characterized by IR, FIR, 1 H - and 31 P NMR, as well as by mass spectra

Single crystals of the compound α -Zn 3 (BO 3 )(PO 4 ) were obtained at 1050 °C by using B 2 O 3 , P 2 O 5 and ZnCO 3 as starting materials and subsequent cooling to 600°C with 20°C/h. X-ray investigations on single crystals yield a new crystal structure in the monoclinic space group Cm - (Nr. 8) with a = 972.5(2); b = 1272.0(3); c = 487.4(3) pm; β = 119.80 (4)°; Z = 4. The structure contains isolated trigonally planar BO 3 and tetrahedral PO 4 units which are not joined together. Zinc occupies three crystallographically different point positions and is trigonal-bipyramidally, tetragonal-pyramidally or distorted tetrahedrally coordinated by oxygen

Cyanobacteria (blue-green algae), Microcystis aeruginosa sp., were isolated from a massive bloom in a eutrophic waterbody in Hungary. Their toxic effect, determined by a mouse test, was associated with the occurrence of microcystins YR and LR which were isolated, separated by means of HPLC procedures and identified by mass spectroscopy. The toxin content of the dry cell material is about 0.22 %, indicating a pronounced toxin-producing ability of the species investigated

Sulphurization is a crucial step during synthesis of phosphorothioate oligonucleotides. Insufficient reaction leads to inhomogeneous products with phosphodiester defects and subsequently to destabilization of the oligomers in biological media. To achieve a maximum extent of sulphur incorporation, various sulphurizing agents have been investigated. Solely, the use of Beaucage reagent provided satisfactory results on PS-PEG supports. Based on our investigations in small scale synthesis (1 μmol) with continuous-flow technique, upscaling to the 0.1-0.25 mmolar range has been achieved using a peptide synthesizer. The syntheses were performed in batch mode with standard phosphoramidite chemistry. Additionally, large scale synthesis of a phosphodiester oligonucleotide has been carried out on PS-PEG with optimized protocols and compared to small scale synthesis on different supports. Products were analysed by 31 P NMR, capillary gel electrophoresis and electrospray mass spectrometry. An extent of sulphurization of 99% and coupling effiencies of more than 99% were obtained and the products proved to have similar purity compared to small scale syntheses on CPG

Halfsandwich thiocarboxylate complexes [CpRu(PR 3 ) 2 (SC(O)CH 2 R′)] ((PR 3 ) 2 = (PPh 3 ) 2 , Ph 2 PCH 2 PPh 2 (dppm), Ph 2 PC 2 H 4 PPh 2 (dppe); R′ = C 6 H 5 , 4-C 6 H 4 Me, 4-C 6 H 4 OMe, 4-C 6 H 4 Cl) are obtained from the corresponding thiolate complexes [CpRu(PR 3 ) 2 SH] and acyl chlorides. The structure of [CpRu(dppm)(SC(O)CH 2 Ph)] was determined: monoclinic space group P2 1 /c (No. 14), a = 9.229(2), b = 16.680(3), c = 21.447(5) Å, β = 90.751(12)°, Z = 4. Reaction of the thiocarboxylate complexes with the anhydrides of either trifluoro-acetic acid or trifluoromethanesulfonic acid gives thioketene complexes [CpRu(dppm) (η 2 -S=C=CHR′)]PF 6 . The structure of [CpRu(dppm)η-S= C = CHPh)]PF 6 was determined: monoclinic space group P2 1 /c (No. 14), a = 13.814(5), b = 15.338(2), c = 17.057(7) Å, β = 93.74(2)°, Z = 4

Reaction of a methanolic copper(II) acetate solution with tetrazolyl enol derivatives 2a or 2b leads to the formation of the corresponding lD-coordination polymer 1 ∞ [CuL 2 ] 3a and pseudo 1D-coordination polymer [CuL 2 ] 2 3b, respectively. On the contrary, reaction of 2c with methanolic copper(II) acetate solution yields OH-bridged 1D-coordination polymer 1 ∞ [CuL 2 (MeOH) 2 3c. Single-crystal X-ray diffraction of the supramolecular species 3 established unequivocally the structures of the stairlike coordination compounds. Reaction of a methanolic copper(II) acetate solution with amidotetrazole derivative 6 leads to the formation of the lD-coordination polymer 1 ∞ [CuL 2 ] 7. The structure of 7 has been established by X-ray structure analysis

The reaction of trifluoronitrosomethane with CH 3 S(O) 2 NH 2 and Na 2 CO 3 as a base in THF gi­ves the yellow liquid CH 3 S(O) 2 NNCF 3 , m.p. 18 °C, which was characterized by vibrational and NMR spectra

Single crystals of [WCl 3 (N 3 S 2 )] 2 were obtained by the reaction of triphenyl-cycIo-1λ 5 antimonia-2,4-dithia-3,5-diazine, SbPh 3 (N 2 S 2 ), with tungsten hexachloride in dichloromethane. Space group P2 1 /n, Z = 2, lattice dimensions at -80°C: a = 744.8(1), b = 923.5(1), c = 1078.7(1) pm, β = 94.43(1)°, R = 0.036. [WCI 3 (N 3 S 2 )] 2 forms centrosymmetric molecules with W 2 N 2 -fourmembered rings and planar cyclo-WN 3 S 2 units

Zr 5 CuSn 3 was prepared from the elements in an arc-melting furnace and investigated by X-ray diffraction of powders as well as of single crystals. The crystal structure was refined from four-circle diffractometer data: P6 3 /mcm, a = 860.04(7) pm, c = 586.80(5) pm, V = 0.3759(1) nm 3 , Z = 2, wR2 = 0.0402 for 371 F 2 values and 15 variables. A refinement of the occupancy parameters re­vealed that the copper position is occupied to only 95.3(8)% in the crystal used for the X-ray investigation. Zr 5 CuSn 3 crystallizes in the Hf 5 CuSn 3 type structure, a filled variant of the Mn 5 Si 3 type. The main features of the Zr 5 CuSn 3 structure are condensed Zr 6 octahedra that are centered by copper atoms

Single crystals of (Me 3 Sn) 3 CCN were obtained by the reaction of tris(trimethylstannyl)amine with boiling acetonitrile in the presence of potassium fluoride and trimethylarsane. The compound has been characterized by IR spectroscopy and by a crystal structure determination. Space group P2 1 /n, Z = 4; lattice dimensions at -50 °C: a = 975.4(1), b = 1316.3(2), c = 1485.3(1), β = 98.55(1)°, R = 0.029. (Me 3 Sn) 3 CCN forms monomeric molecules with a linear CCN axis (bond angle 178.7(6)°) and bond lengths of CC = 142.1(8) pm and CN = 114.5(8) pm

The crystal structures of PbMe 3 I and BiPh 2 Cl have been determined by X-ray methods. Both compounds form polymeric chains via bent μ 2 -halogeno bridges and almost linear X-M-X units (X = I, Cl). PbMe 3 I: Space group P2 1 2 1 2 1 , Z = 2; lattice dimensions at -50 °C: a = 653.0(1), b = 1034.0(2), c = 1124.5(2) pm, R = 0.049. BiPh 2 Cl: Space group P4 2 , Z = 4; lattice dimensions at -50 °C: a = b = 847.5(2), c = 1644.9(4) pm, R = 0.044