Band 54, Heft 12

The title compound was prepared by reaction of elemental calcium with the calcium metaperrhenate Ca(ReO 4 ) 2 . Its crystal structure was determined from single-crystal X-ray data: Amm2, a = 560.31 (5)pm, b = 1572.4( 1)pm, c = 719.91 (6)pm ,Z = 2 ,R = 0.033 for 930 structure factors and 46 variable parameters. The calcium atoms occupy three atomic sites, all with seven oxygen neighbors. Of the two different rhenium atoms one has square-pyramidal oxygen coordination with an average oxidation number +6.25. The other rhenium site (oxidation number +7) was refined as a split position with trigonal-bipyramidal (75%) and tetrahedral oxygen coordination (25%). One oxygen site remains unoccupied, whenever the tetrahedral rhenium site is occupied, resulting in the composition Ca 5 Re 3 O 14.75 . A test for superconductivity of this black compound down to 1.5 K was negative.

The title compound was prepared by solid state reaction of Ag 2 O with Hg(NO 3 ) 2· H 2 O in air at 350 °C. Its crystal structure was determined from single-crystal diffractometer data: Pnma, a = 620.1(1) pm, b = 670.1(1) pm, c = 1267.5(2) pm, Z = 4, R = 0.026 for 586 structure factors and 33 variable parameters. The compound may be represented by the formula Ag(HgO) 2 NO 3 . The mercury(II) together with the oxygen atoms form zig-zag chains with linear coordination of the mercury atoms. The oxygen atoms of these chains are linked via silver(I) atoms, thus forming two-dimensionally infinite nets, which contain the trigonal planar nitrate groups in interstices. Thus, only secondary Hg-O and Ag-O bond are formed between the nets.

An improved synthesis of arylxenon(II) salts is reported. The series of fluoro-containing arylxenon(II) tetrafluoroborates (aryl = C 6 F 5 , 2,3,4,5-C 6 HF 4 , 3,4,5-C 6 H 2 F 3 and 3,5-C 6 H 3 F 2 ) are prepared by the reaction of xenon difluoride with the corresponding aryldifluoroboranes. The salts [C 6 F 5 Xe] [BF 4 ] and [2,3,4,5-C 6 HF 4 Xe] [BF4] are long-term stable in anhydrous HF (aHF) solution at rt, while [3,4,5-C 6 H 2 F 3 Xe] [BF 4 ] and [3,5-C 6 H 3 F 2 Xe] [BF 4 ] are converted into 1,2,3,5-tetrafluorobenzene and 1,3,5-trifluorobenzene, respectively, within a few hours.

The title compounds were obtained by reacting stoichiometric quantities of the corresponding dialkalimonochalcogenide, germanium powder and chalcogen at 1073 K. The four compounds are isostructural, crystallizing in space group C2/c, Z = 4 with K 4 Ge 4 S 10 : a = 15.161(3), b = 15.198(2), c = 8.760(2) Å, ß = 105.36(3)°, Rb 4 Ge 4 S 10 : a = 15.282(7), b = 15.341(7), c = 9.061(4) Å , ß = 106.10(3)°; Rb 4 Ge 4 Se 10 : a = 16.095(9), b = 16.09(1), c = 9.390(7) Å , ß = 105.79(2)° and Cs 4 Ge 4 Se 10 : a = 16.348(9), b = 16.49(1), c = 9.771(3) Å, ß = 107.10(3)°. Their crystal structures were solved and refined from single crystal diffractometer data (MoKα radiation) obtained at 294 K. They are characterized by the formation of discrete adamantanelike complex anions [Ge 4 Q 10 ] 4- which are arranged in slabs parallel to (010). Mean Ge-S bond lengths are 2.202 A for K 4 Ge 4 S 10 and 2.186 Å for Rb 4 Ge 4 S 10 while the mean Ge-Se bond length in both selenides amounts to 2.332(3) Å. Terminal and bridging Ge-Q bonds differ by at least 0.1 Å. The atomic arrangement corresponds to that of Tl 4 Ge 4 S 10 .

Colorless crystals of the new thiostannate Rb 6 Sn 2 S 7 were obtained by reacting a stoichiometric melt of Rb 2 S, Sn and S at 700°C. The compound is orthorhombic, oP60, s.g. P2 1 2 1 2 1 (No. 19) with a = 9.982(4), b = 13.45(1), c = 15.20(1) Å; Z = 4. The crystal structure was determined from diffractometer data and refined to a conventional R of 0.043 (1380 Fo's, 137 variables). The crystal structure contains dimeric anions, [Sn 2 S 7 ] 2 - , which are built up by slightly distorted SnS 4 tetrahedra sharing a common sulfur atom. The mean Sn-S bond length calculates as 2.384 Å, the bond angle on the bridging S is 110.4°. The structure contains six independent Rb-cations which are coordinated to 5-6 sulfur atoms in irregular configurations.

The discrete complex [(Cul) 2 (pyzCN) 4 ] (1) and the coordination polymers 1 ∞ [CuI(pyzCN)] (2) and 3 ∞ [(CuX) 3 (pyzCN) 2 ] (3, 4; X = Br, Cl) may be prepared from the respective copper(I) halide CuX and 2-cyanopyrazine (pyzCN) by self-assembly in acetonitrile solution at 100- 120°C. Whereas 2 exhibits 1 [Cul] staircase double chains as its characteristic substructure, the three-dimensional networks of 3 and 4 contain single zigzag CuX strings. The influence of the copper(I) halide on both the connectivity pattern and the dimensionality of a resulting coordination network is particularly apparent for the 1:1 complexes 1 ∞ [CuI(pymMe)] (5), 3 ∞ [(CuBr) 3 (pymMe) 3 ] (6) and 2 ∞ [CuCl(pymMe)] (7), which were generated by reaction of CuX with 4-methylpyrimidine (pymMe) under reaction conditions similar to those above.

Using an extended X-ray absorption fine structure (EXAFS) technique, the formation constant of the pentaaquachloroiron(III) complex was determined to be 3.8 ± 0.4 mol -1 dm 3 at 25.0 ± 0 .1 °C in a 1.00 mol dm -3 HCIO 4 aqueous solution. The structures of [Fe(OH 2 ) 6 ] 3+ and [FeCl(OH 2 ) 5 ] 2+ were determined on the basis of the same EXAFS data. The Fe-O bond length (2.05 Å) in the latter is longer than that (2.01 Å) in the former due to the electron donation and charge neutralization by the coordinating chloride ion with the Fe-Cl bond length of 2.26 Å.

(CH 3 NH 3 ) 2 Sb 2 S 4 has been isolated from the reaction of antimony with sulfur in the presence of manganese in an ethanolic solution of methylamine under solvothermal conditions. Two pyramidal SbS 3 units are linked via common S-S edges to give dimeric Sb 2 S 4 2- anions, which are joined via secondary Sb···S contacts of 3.074(2) and 2.975(2) Å forming infinite 1 ∞ [SbS 2 ] -2n chains consisting of edge-linked ψ-SbS 4 trigonal bipyramids. The cis configuration of the Sb 2 S 4 2- anions in the title compound is observed for the first time. A specific hydrogenbonding pattern between the amino-hydrogen and the sulfur atoms stabilizes this configuration and gives rise to anionic layers separated by the methyl groups.

The molecular structure of tris(dimethylarsino)amine has been determined by X-ray diffraction methods. The compound has a planar AS 3 N core unit with a paddle-wheel conformation of the three Me 2 As groups. This structure was also confirmed by density functional calculations.

Nucleophilic phosphanylation of ortho-fluorophenylacetic acid or ortho-fluorobenzylamine with PhPH 2 using KOtBu as the base affords the hydrophilic tertiary phosphanes 3 and 4a with terminal CH 2 -COOH and CH 2 -NH 2 substituents. The corresponding secondary phosphane ligands 2 or 5 may be obtained by Pd-catalyzed P-C coupling of ortho-iodophenylacetic acid with PhPH 2 or selective nucleophilic phosphanylation of ortho-fluorophenylacetic acid. Novel phosphonatomethyl derivatives 7a, 7b of triphenylphosphane have been obtained in a two stage synthesis using ortho-iodobenzylchloride or meta-iodobenzylbromide as starting materials. Arbusov reaction with P(OEt) 3 and Pd-catalyzed P-C coupling reactions with Ph 2 PH gave the esters 7a, 7b. Purification of 7a was achieved via its BH 3 adduct 8a. Deprotection, hydrolysis and neutralisation with NaOH affords the water soluble sodium salts 9a,9b. α-Hydroxy and α-benzylamino derivatives 12 and 14 of ortho-diphenylphosphanobenzyl phosphonate (e.g. 7a) and the corresponding Me 2 P(O) analogs 13 and 16 are accessible in a straightforward manner by addition of (MeO) 2 P(O)H or Me 2 P(O)H to ortho-phosphanobenzaldehyde 11a or its benzaldimino derivative 15, respectively. An improved synthesis for 11a -11c has been developed. Reaction of 11a with the Wittig reagent Ph 3 P=C(H)COOEt and subsequent hydrolysis of the intermediate ester 17a affords ortho-diphenylphosphano cinnamic acid 17. The catalytical activity of 1,9a, 9b and related ligands in Suzuki-type coupling reactions has been investigated.

Reactions of aminated cyclotri- and cyclotetra-phosphazenes, viz., N 3 P 3 L 6 and N 4 P 4 L 8 (L = -NC 4 H 8 O, -NC 5 H 10 , -HNC 6 H 11 and -HNC 8 H 17 ) with W(CO) 6 have been studied. [(N 3 P 3 L 6 )W(CO) 3 ] derivatives are obtained with N 3 P 3 L 6 while N 4 P 4 L 8 yield tetracarbonyl substituted derivatives, [(N 4 P 4 L 8 )W(CO) 4 ]. Mixed ligand tungsten tricarbonyls of the type [C 12 H 8 N 2 )(N 3 P 3 L 6 or N 4 P 4 L 8 )W(CO) 3 ] have also been synthesized with [(o-phen)W(CO) 4 ].

The reaction of Me 2 P(:X)H [X = O: 1; X = S: 4] with paraformaldehyde furnished the α - hydroxyphosphine oxide 2 and sulfide 5 which, upon treatment with p-toluenesulfonyl chloride, were converted into the tosylated derivatives 3 and 6. The diphosphorylated glucosyl compound 8 was synthesized by reaction of two equivalents of tosylated phosphine oxide 3 with benzyl 4,6- O-benzyliden-α-D-glucopyranoside 7. The spacer phosphorylated glucosyl derivatives 10 and 11 were formed in the reaction of γ -bromopropyl-2,3,4,6-tetra-0 -benzyl-β-D-glucopyranoside 9 with triethylphosphite and triphenylphosphine.

Three novel Schiff bases: salicylaldehyde methanesulfonylhydrazone (1), 2-hydroxyacetophenone methanesulfonylhydrazone (2) and 2-hydroxy-1-naphthaldehyde methanesulfonylhydrazone (3) have been synthesized. Compounds 1-3, as well as acetone methanesulfonylhydrazone (4) have been characterized by TLC, 1 H NMR and IR spectra. The spectroscopic results for 1-3 have revealed the presence of an intramolecular hydrogen bond between the hydroxyl group and the imine N atom. The conformational isomerism of 1-4 with respect to the rotations around the SN and NN bonds have been studied by the method of molecular mechanics. Compounds 1-4 and methanesulfonylhydrazine exhibit antibacterial and cytotoxic effects.

Reaction of 3 equivalents of ZrCl 4 · 2Et 2 O (1) with 1 equivalent of (Et 2 N 4 Zr in diethyl ether readily affords crystalline (Et 2 N)ZrCl 3 · 2Et 2 O (2) in almost quantitative yield. The product was characterised by elemental analysis and by 1 H. 13 C NMR, and MS techniques. The reactivity of this reagent towards C-H acidic compounds has been studied using cyclopentadiene as a C-H acid. The crystal structures of both 1 and 2 have been determined by X-ray diffractometry. The coordination polyhedra reveal a nearly perfect octahedral geometry with a trans Et 2 O ligation for 1 and a cis one for 2.

Several new 4H-pyrano[2,3-h]coumarines 5a-e were prepared by the reaction of 7-hydroxycoumarine with cinnamonitriles 1. Also, the reaction of 7-hydroxycoumarine with a mixture of aliphatic aldehydes and malononitrile afforded compounds 5f,g. Similarly, 4-hydroxycoumarine was reacted with the same reagents to give compounds 9a-g. The reaction of 9 g with different nucleophilic reagents afforded the pyrimido[4′,5′:6,5]pyrano[3,2-c]coumarin-4-one derivatives 10-12, 4-methyl-2-(ethoxymethylenamino)4H-pyrano[3,2-c]coumarine-3-carbonitrile (13) and pyrazolo[3′,4′;6,5]pyrano[3,2-c]coumarine (14) respectively.

The cyclic voltammograms of 1-cyano-2-hydroxy-1,2-dihydrofullerene derivatives indicate a complex redox behavior. The first reduction peak of these new compounds is at less negative values compared to the parent [60]fullerene. This is a consequence of the two electronwithdrawing groups, which are attached directly to the C 60 moiety.

Dehydrogenation of the N-[2-(aminocarbonyl)phenyl]piperidines 1 -5 using Hg(II)-EDTA, generated the quinazolinones 6 -9 . Increasing size of the 4-substituent in the piperidine decreased the oxidation rate and the product yield. N-[2-(Hydroxyiminomethyl)phenyl]piperidines 18-22 showed a different behaviour. While 18 with H g(II)-EDTA in water produced the oxime lactam 24 in quantitative yield, the 4- substituted piperidines 19-21 caused not only a lower reaction rate but also an altered product pattern. The double dehydrogenation to lactams was reduced and the cyclic nitrones, formed by two electron withdrawal, became dominant. From the spiro compounds 21 and 22, solely the quinazoline-N-oxides 29 and 30 resulted. The mechanism of the reactions is discussed.

The thiocarboxamidocinnamonitriles (2) reacted with 2-hydrazinothiazol-4(5H)-one (3) to afford the corresponding pyrano[2,3-d]thiazoles (6). Compounds 6 were used for the synthesis of several new annelated pyran, thiazole, 1,2,4-triazole and 1,2,4-triazine derivatives via their reactions with chloroacetic acid, ethyl chloroformate, diethyl oxalate and acetylacetone. Structures were established based on elemental and spectral data studies. Some of the newly synthesized heterocyclic derivatives were tested for their antimicrobial activity.

The X-ray crystal structure of the 1:1 adduct shows a complicated network of water and 2-pyrrolidinone molecules where the carbonyl oxygen atom of 2-pyrrolidinone forms hydrogen bonds with protons of two separate water molecules and the NH proton of the 2- pyrrolidinone molecule interacts with the oxygen atom of a third water molecule.

X-ray crystal structure data for the title compound dihydrobenzofuryl-pyrazolo[4,3-d]pyrimidin- 7-one (2) reveal that the two bicyclic heteroaryl systems are virtually coplanar along their joint C (5)-C(11) axis with an interplanar angle of 1.13°. This planar conformation is held by an intramolecular hydrogen bond between the pyrimidinone N(6)-H and the O(17) lone pair of the dihydrobenzofuryl moiety. The spatial interatomic distance for O(17)-N(6), determined as 2.04 Å, favours this H-bridge.

1-Methyl-2-(methylthiomethyl)-1H- benzimidazole (mmb, N^S) was reacted with Ph 3 PAuCl/AgPF 6 in THF to yield [(Ph 3 P)Au(mmb)](PF 6 ) which could be crystallographically characterized. The Au + ion is almost linearly coordinated by the triphenylphosphine P and the imine N atom of a monodentate N^S ligand. There is no gold(I)-sulfur bonding as the distance of ca. 3.02 Å indicates. Similarly, close intermetallic contacts between the gold centers are absent. Both effects are attributed to the positive charge on the metal.

Blue moisture sensitive single crystals of [YbCl 2 (THF) 5 ] + [WOCl 4 (THF)]- were obtained as a by-product from the reaction of the ytterbium trisamide Yb[N(SiMe 3 ) 2 ] 3 with tungsten hexachloride in THF solution. The crystals were suitable for an X-ray crystal structure determination. Space group P2/c, Z = 2, lattice dimensions at -80 °C: a = 1192.5(1), b = 1117.1(1), c = 1349.9(1) pm, ß = 104.115(7)°, R = 0.0424. The structure consists of cations [YbCl 2 (THF) 5 ] + in which the ytterbium atom is coordinated in a pentagonalbipyramidal way by the chlorine atoms in the axial positions and by the oxygen atoms of the THF molecules in equatorial positions. Counterions are the well-known [WOCl 4 (THF)] - ions.

Colourless single crystals of Ph 3 AsCl 2 as well as of β-Ph 3 AsBr 2 were obtained from acetonitrile solutions and were suitable for X-ray structure determinations. Ph 3 AsCl 2 : Space group P2 1 2 1 2 1 , Z = 4, lattice dimensions at -90 °C: a = 1247.9(2), b = 1267.5(1), c = 1033.4(1) pm, R x = 0.0484. β-Ph 3 AsBr 2 : Space group P1̄ , Z = 4, lattice dimensions at -80 °C: a = 949.1(1), b = 1189.7(1), c = 1693.7(2) pm, a = 98.32(1)°, ß = 103.64(1)°, γ = 109.44(1)°, R x - 0.0628. The structures consist of Ph 3 AsX 2 molecules (X = Cl, Br) with trigonalbipyramidal coordination of the arsenic atom with the halogen atoms in the axial positions.

The redetermination of the crystal structure of α-iodine monochlorideα-ICl, is described. It crystallises monoclinically in the space group P2 1 /c with a = 1216.2(1), b = 428.6(1), c = 1188.9(1) pm, ß = 117.50(1)° and eight formula units per unit cell.

Condensation of 1-oxo-1,2,3,4-tetrahydrocarbazoles 1a-e and o-aminoacetophenone 2 under acid catalysis afforded a new class of quino[2,3-a]carbazoles 3a-e in good yields. A plausible mechanism for the product formation is also proposed.