Volume 55, Issue 6

3,3,5,5-Tetraphenyl-1,2,4-trithiolane (1) reacts with twofold excess of (Ph 3 P) 2 Pt(η 2 -C 2 H 4 ) (4) to give a 1:1 mixture of the complexes (Ph 3 P) 2 (6a) and (Ph 3 P) 2 Pt(η 2 -Ph 2 C=S) (7a). Treatment of 3,3,6,6-tetraphenyl-1,2,4,5-tetrathiane (2) with a fourfold excess of 4 yields [Pt 2 (PPh 3 ) 4 (μ-S) 2 ] (8) and the platinum(O) compound 7a. The reaction of the 1,2,3,5,6- pentathiepane 3 with a fourfold excess of 4 affords a 1:1:1 mixture of 8, the platinum(O) complex 7b and the bis-thiolato platinum(II) complex 6b. The thioketone complexes 7a-c were formed in smooth reactions of 4 with the thioketones 5a-c. The molecular structure of (Ph 3 P) 2 Pt(η 2 -Ph 2 C=S) (7a) has been established by single-crystal X-ray analysis.

A series of silicon-accumulating plants [different Equisetum (horse tail) species, Echium vulgare, and Symphytum officinale] were studied by solid-state 29 Si NMR experiments. For this purpose, selected parts of these plants were freeze-dried and then investigated by solid-state 29 Si VACP/MAS NMR spectroscopy. The 29 Si NMR spectra of these plants are quite similar and exhibit the typical pattern characteristic of polysilicic acid (amorphous silica).

The reaction of [Ru(tpy)(PPh 3 )(Cl) 2 ] (tpy = 2,2′:6′,2″-terpyridine) with sodium azide in acetone/water afforded [Ru(tpy)(PPh 3 )(N 3 )2]. The new Ru-diazide complex was fully characterized by elemental analysis, IR, Raman, and multinuclear NMR spectroscopy. The structures, energies and vibrational frequencies of the ruthenium diazide isomers, cis- and trans- [Ru(tpy)(PMe 3 )(N 3 ) 2 ] (Me=CH 3 ), were calculated at the semi-empirical ZINDO/1 level of theory.

The 2-dimensional coordination polymers 2 ∞ [{(CuI) 2 (Mepyz) 2 } · Mepyz] (1a), 2 ∞ [CuX(Mepyz)] (2a, X = Br; 2b, X = Cl) and 2 ∞ [(CuX) 2 (Mepyz)] (3a, X = I;3b, X = Br) may be prepared by reaction of the appropriate copper(I) halide with 2-methylpyrazine (Mepyz) either in acetonitrile solution at 130 °C (2a/2b, 3a/3b) or without solvent at 20 °C (la). Mepyz ligands bridge (CuI) 2 rhomboid dimers in the chiral network of la, whose resulting 24-membered rings are large enough to accomodate an Mepyz guest molecule, la rapidly loses these guests to afford a crystalline powder (lb), that can reversibly imbibe benzonitrile molecules into its open channels. In contrast to la, the sheets of 2a/2b contain zigzag infinite CuX chains, those of 3a/3b staircase 1 ∞ [CuX] double chains as their characteristic substructures. Helical 3 ∞ [CuI] single chains in the 3-dimensional network of 3 ∞ [CuI Mepip)4 are bridged by R-2-methylpiperazine (Mepip) ligands in a second example of a chiral coordination polymer.

By treatment of RhCl 3 or IrCl 3 with K 2 C 2 O 4 the bis(oxalato)metallates trans-K 3 [RhCl 2 (C 2 O 4 ) 2 ] and cis-K 3 [IrCl 2 (C 2 O 4 ) 2 ] are formed. From the aqueous solutions single crystals were grown by slow diffusion of ethanol and X-ray structure determinations of trans-K 3 [RhCl 2 (C2O 4 ) 2 ] · 4 H 2 O (monoclinic, space group I2/m, a = 6.218(1), b = 11.837(2), c - 10.357(2) Å, β = 95.55(3)°, Z = 2) and cis-K 3 [IrCl 2 (C 2 O 4 ) 2 ] · H 2 O (monoclinic, space group /2/a, a = 14.060(3), b = 7.586(2), c = 23.488(5) Å, β = 90.44(3)°, Z = 8) have been performed. The oxalato and chloro ligands of the complex anions are connected via hydrogen bonds and electrostatic interactions to water molecules and potassium ions. The potassium ions are eightfold and in one case ninefold coordinated.

By electrochemical oxidation of (n-Bu 4 N) 2 [B 9 H 9 ] in the presence of nitrite ions and the base DBU in dichloromethane solution [1-(NO 2 )B 9 H 8 ] 2- is formed. X-ray diffraction analysis has been performed on a single crystal of (Ph 4 P) 2 [1-(NO 2 )B 9 H 8 ] · CH 3 CN (monoclinic, space group P2 1 a = 10.643(5), b = 32.661(5), c = 13.924(5) Å, β = 96.68°, Z = 4). By reduction of [1-(NO 2 )B 9 H 8 ] 2- with FeSO 4 in aqueous alkaline solution the amino derivative [1-(NH 2 )B 9 H8] 2- is formed. The UB NMR spectra of both compounds are consistent with a monosubstituted tricapped trigonal prism. The IR and Raman spectra exhibit characteristic BB, BH, NO and NH vibrations, respectively.

By reaction of (n-Bu 4 N) 2 [ReBr 6 ] with pyridine and (n-Bu 4 N)BH 4 in dichloromethane various bromo-pyridine-rhenium(III) complexes are formed which can be separated by chromatography. Electrochemical oxidation of (n-Bu 4 N) 2 [ReBr 5 Py] leads to (n-Bu 4 N)[ReBr 5 Py]. X-ray structure determination on a single crystal has been performed of (n-Bu 4 N)[ReBr 5 Py] (monoclinic, space group P2 1 /n a = 11,248(5), b = 17,192(5), c = 15,206(5) Å, β = 97,600(5)°, Z = 4).

The results of single crystal X-ray structure determinations are reported for monoclinic (NMe 4 ) 2 Li(H 2 O) 2 [Cr(CN) 6 ] (a = 1736.7(2), = 888.0(1), c = 1659.3(1) p m ,β = 119.33(1)°; C2/c, Z = 4) and orthorhombic (NMe 4 ),Na(H 2 O)[Cr(CN) 6 ] (a = 960.0(2), b = 885.0(2), c = 1269.8(3) pm; Pnmm, Z = 2) and (NMe 4 ) 2 Na(H 2 O)[Co(CN) 6 ] (a = 1854.5(4), b = 853.5(1), c = 1328.7(3) pm; Pnma, Z = 4), the latter exhibiting a superstructure of the NaCr compound. The average distances within the hexacyano groups are Cr-C: 207.8 resp. 208.3 pm and Co-C: 189.5 pm. The alkali ions are incorporated into the elpasolite-like arrangement of the bigger ions as di- or monohydrated species [Li(H 2 O) 2 ] + and [Na(H 2 O)] + resp., becoming tetrahedrally coordinated [LiO 2 N 2 ] and [NaON 3 ] within the lattice and fixed by hydrogen bridges O-H...N as well. Some structural details and relations are discussed.

N,N′-Tetramethyl-N"-benzoylphosphoryltriamide (I) and dimorpholido-N-benzoylphosphorylamide (II), and their sodium salts Nal, Nall were synthesized and characterized by means of IR and 1 H, 31 P NMR spectroscopy. The structures of I, II were determined by X-ray diffraction: I monoclinic, space group P2i/c with a = 10.162(3), b= 11.469(4), c = 12.286(4) Å , β = 94.04°, V = 1428.4(8) A 3, Z = 4, p (calcd) = 1.187 g/cm 3 ; II monoclinic, space group C2/c with a = 15.503(4), b = 10.991(3), c = 22.000(6) Å, β = 106.39°, V = 3596.3(17) Å 3 , Z = 8, p (calcd.) = 1.253 g/cm 3 . The refinement of the structures converged at R = 0.0425 for I, and R = 0.068 for II. In both structures the molecules are connected into centrosymmetric dimers via hydrogen bonds formed by the phosphorylic oxygen atoms and hydrogen atoms of amide groups.

The crystal structure of bis(triethylammonium)closo-decahydrodecaborate [bis(triethylammonium) decaboranate(10)], [(C 2 H 5 ) 3 NH] 2 [B 10 H 10 ], was determined and refined (space group Pmmn, no. 59, a = 989.7, b = 1333.7, c = 903.7 pm). The compound is a versatile starting material for many substances containing the [BioHio]2- entity and its derivatives. The closo-[B 10 H 10 ] 2- cluster is a bicapped square antiprism which is only slightly distorted. Its deviation from D 4d symmetry is smaller than that of the B 10 cages in every other compound containing this entity that have been structurally characterised. The presence of additional (N )H ---B 3 interactions in form of multiple-centre bonds between the cations and the anions, which were postulated earlier and which should influence the cage symmetry, could not be confirmed. At 55 °C, the transition into a high temperature phase was investigated by X-ray powder diffraction. The high temperature phase crystallises in the tetragonal crystal system (a = 946.9, c = 1351.0 pm).

The lithium derivative of di(isopropyl)aminofluorosilylhydrazine cyclizes with formation of a five-membered silylhydrazine ring system (1). The analogous reaction of di(tert-butyl)- fluorosilylhydrazine gives the six-membered silylhydrazine ring system (2 ). 1 isomerizes thermally to the six-membered cyclic silylhydrazine 3. LiF-elimination from lithiated (Me 3 C) 2- SiFNHNHSiF(CHMe 2 ) 2 leads to the formation of the six-membered cyclic silylhydrazine 4, [(Me 2 HC) 2 Si-NH-NSiF(CMe 3 ) 2 ] 2 . Symmetrical six-membered tetra(fluoro)silylhydrazine rings, (F 2 SiNRNR) 2 (5: R = SiMe 3 , 6: R = SiMe 2 CMe 3 ) are obtained in the reaction of bis(trifluorosilyl)hydrazines with dilithium-bis(silyl)hydrazides, whereas a five-membered unsymmetrical silylhydrazine (7: (RNSiF 2 ) 2 N-NR' 2 , R = SiMe 2 CMe 3 , R′ = SiMe 3 ) is formed in the reaction of R(SiF 3 )N-N(SiF 3 )R and R'(Li)N-N(Li)R'. In the reaction of the same fluorosilylhydrazine with dilithiated N,N'-diphenylhydrazide the unsymmetrical six-membered ring 8 is obtained. The crystal structures of 1, 2 and 3 are reported.

Reduction of 2-cyanopyridine by sodium in dry methanol in presence of thiosemicarbazide produces 2-pyridineformamide thiosemicarbazone, HAm4DH. The crystal structure of HAm4DH, which has a number of intermolecular interactions involving its five NH hydrogen atoms, has been solved. Crystal structures of the complexes prepared by reaction of HAm4DH with zinc(II) chloride, bromide and iodide have also been obtained. Neutral HAm4DH is coordinated via the pyridyl nitrogen, imine nitrogen and thione sulfur atoms, and each complex is five-coordinate with two halogen ligands. The structures of the three complexes are best described as square pyramidal with [Zn(HAm4DH)l 2 ] having the largest distortion toward a trigonal bipyramid.

Ylidyl chlorophosphanes 1 and dichlorophosphanes 2 react with trimethylsilyl phosphanes to yield the ylidyl diphosphanes 3, 4,5, 7 and the 2-ylidyl triphosphanes 8. From the reaction of compounds 1 with lithium diphosphanyl amide and diphosphanyl methanide result the ylidyl diphosphonium ylides 11 and ylidyl diphosphinimines 13. The former rearrange to give the ylidyl triphosphanyl methanes 12. The chloromethyl diphosphinimine 13c enters a cyclization to give the 1,2,3,5-azatriphosphole derivative 14, the structure of which has been solved by X-ray analysis. From the reaction of ylidyl bis(chlorophosphanes) 17 and 20 with the same reagents the 1,2,4,5-tetraphosphinine derivative 18 and the 1,2,3,5,6-azatetraphosphinine derivatives 19 and 21 are obtained.

A series of halfsandwich ruthenium sulfinato complexes [CpRu(PR' 3 ) 2 (SO 2 R)] (R = Me, CH 2 Ph, C 2 H 4 Ph, Ph, 4-C 6 H 4 Me; PR' 3 = PMe 3 , 1/2 dppm) with various electronic and steric environments around the ruthenium centre, have been prepared by insertion of SO 2 into a ruthenium carbon bond, by a direct ligand exchange reaction, or by oxidation of thiolato complexes with 3-chloroperoxybenzoic acid. The chiral complexes [CpRu(CO )(PPh 3 )(SO 2 R)] (R = Me, CH 2 Ph, Ph) were obtained similarly by oxidation of the corresponding thiolates with magnesium monoperoxyphthalate. Alkylation of the sulfinato complexes with oxonium salts [R" 3 O]X (R" = Me, Et; X = BF 4 , PF 6 ) gave ruthenium complexes of sulfinic acid esters, [CpRu(L)(L′)(S(O)(OR″)R)]X in high yields and, for the chiral complexes, up to 82% de. The esters may be detached from the metal by ligand exchange with acetonitrile. Stronger nucleophiles such as I - or SMe - dealkylate the coordinated sulfinic acid esters.

Compounds of the general formula (CH 3 NH 3 ) n-1 (CH 3 C 6 H 4 CH 2 NH 3 ) 2 Pb n X 3n+1 , where X = I, Br, Cl and n= 1,2, 3,..., were prepared and characterized analytically and spectroscopically. Moreover, (CH 3 C 6 H 4 CH 2 NH 3 ) 2 PbX 4 and (CH 3 NH 3 C 6 H 4 CH 2 NH 3 ) 2 Pb 2 I 7 were characterized by X-ray crystal structure analysis. Their optical absorption and photoluminescence spectra exhibit excitonic bands, even at room temperature.

The solid-state structures of a l-(φ-ammoniopropyl)-2-(2-thienylcarbonyl)-cyclopentadienide (2) and a l-(φ-ammoniopentyl)-2-(4-methoxybenzoyl)-cyclopentadienide (3) have been determined. Both betaines self-assemble by NH ··· O hydrogen bonds, but the motifs are different. In the ammoniopropyl case, both intramolecular and intermolecular hydrogen bonds of this type exist, the latter bond being responsible for the formation of infinite chains. In the ammoniopentyl case, intermolecular hydrogen bonds build up a two-dimensional network which contains centrosymmetric dimers held together by NH ··· O=C-aryl hydrogen bonds.

The synthesis and antimicrobial activity of a series of the title thiones were examined. Reaction of such thiones with hydrazonoyl halides, resulted in ring transformation to give 5-acylhydrazono derivatives of 1,3,4-thiadiazoles. The mechanisms of the studied reactions are discussed.

The reaction of arsenic, MgSO 4 and S 2 Cl 2 in acetonitrile yielded the title compound along with 4,5- dichloro-1 ,2,3-dithiazolium chloride, [C 2 NS 2 Cl 2 ]Cl (which was formed from the solvent and S 2 Cl 2 ). The crystal strucutre of [Mg(NCCH 3 ) 6 ][As 4 Cl 14 ] was determined by X-ray diffraction. It is triclinic, space group P1¯, Z = 2, R = 0.049. The Mg 2+ ion is coordinated by six acetonitrile ligands. The anions consist of AsCl 4 - and AsCl 3 units which are associated to chains along the a axis by As ··· Cl contacts. Each As atom has distorted octahedral coordination.