Volume 46, Issue 1

1,13-Bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane-dimercury(I)-diperchlorate is formed by the reaction of 1,13-bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane in ethanol with an aqueous solution of dimercury(I)-diperchlorate. It crystallizes in the triclinic space group P Ī with a = 1020.6(2), b = 1200.6(8), c = 1441.1(6) pm , α = 69.60(5)°, β = 83.04(13)°, y = 66.53(4)° and Z = 2. The crystal structure was determined by X -ray diffraction and refined to an R-value o f 0.079. The Hg 2 2+ -ion is coordinated to both nitrogen atoms and four oxygen atoms of one molecule of the ligand. By changing four C - O torsional angles from trans to gauche, the ligand adopts a helical, chiral configuration around the Hg 2 2+ -ion. The CIO 4 - -ions are not coordinated to the Hg 2 2+ -ion.

High yield syntheses of the new diaminosulfanes (CH 3 SO 2 ) 2 NSN (SO 2 CH 3 ) 2 (1) and (CH 3 SO 2 ) 2 NSSN (SO 2 CH 3 ) 2 (2) are reported. 1 is obtained by the action of elemental sulfur on (CH 3 S O 2 ) 2 NCl and by metathesis of (CH 3 SO 2 ) 2 N Ag with SCl 2 , 2 by the analogous metathesis with S 2 Cl 2 . 2 is converted to 1 by partial desulfurization with (C 6 H 5 ) 3 P. 1 and 2 are active transfer reagents of the S 2⊕ or S 5⊕ group, respectively. Thus, the reaction o f 1 or 2 with n -butanol gives the alkoxysulfanes C 4 H 9 OS n OC 4 H 9 (n = 1, 2), and their reaction with [(CH 3 ) 3 Si] 2 NH leads to the silylated diaminosulfanes [(CH 3 ) 3 Si] 2 NS n N[Si(CH 3 ) 3 ] 2 (n = 1, 2). The crystal structures of the title com pounds were determined at - 9 5 °C. The most important features of the structure of 1 are the near planarity of the three bonds around the nitrogen atoms (sum of bond angles 356.9 ), the distances N - S II 169.7 and N -S VI 171.5 pm , and the N - S II -N bond angle o f 105.3° (mean values for two independent molecules). In 2, both nitrogen atoms have a planar geometry (sum of bond angles 360.0°; distance from the plane of their bonded atoms ≤ 2 pm). All N - S bond lengths are approximately equal (mean values: N - S II 170.4, N - S VI 170.7 pm). The S - S bond length is 202.1 pm. The torsion angle N - S - S - N of -8 5 ° lies in the usual range for disulfides X - S - S - Y . For comparison, the known structure of CH 3 - N (SO 2 CH 3 ) 2 was redetermined at - 9 5 °C.

Reaction of TcO 7 with (CH 3 ) 4 Sn yields besides {(CH 3 ) 3 SnOTcO 3 } n (5) also CH 3 TcO 3 (4) and [(CH 3 ) 2 TcO 2 ] 2 (3). 5 is not isomorphous with {(CH 3 ) 3 SnOReO 3 } n (6), the trimethylstannyl perrhenate, though both compounds have a zickzack chaine structure. 5 is monoclinic (C 2h 5 -P2 1 /c) with a = 961.6(9), b = 764.5(6), c = 1190.1(7) pm, β = 91.16(7)°, Z = 4, V = 874.71 × 10 6 pm 3 , d rö = 2.48 g/cm 3 . While 6 possesses a crystallographic mirror plane 5 does not.

Normal coordinate analyses for the ten isotopomers Cs 2 11 B n 10 B 6-n I 6 , n = 0 - 6 , including the pairs of geometric isomers for n = 2, 3, 4 have been performed, based on a general valence force field. Using a set o f 8 force constants (e.g. f d (BB) = 1.45, f d (BI) = 2.33 mdyn/Å ) the calculated frequencies are in good agreement with observed IR and R am an bands measured at 10 or 80 K for Cs 2 B 6 I 6 with natural abundance of B isotopes (~80% 11 B , 20% 10 B) as well as for 11 B and 10 B enriched derivatives. From the calculated atomic displacements and the potential energy distribution the classification in the 30 times more intense substituent (in-phase motions of B and I, ≤ 153 cm -1 ) and the weak cage vibrations (anti-phase displacements of B and I, ≥ 385 cm -1 ) is deduced. Only the cage modes show characteristic band patterns, explained by the superposition of the calculated spectra of the different isotopomers in accordance with their statistical abundance. There is an excellent conformity for the total symmetric A, vibration, but for the triply degenerate T lu and T 2g modes as a consequence of lowered site symmetry in the solid state more bands than calculated are observed.

1 Tetraphenylphosphonium tetrathiometalates, (PPh 4 ) 2 MS 4 (M = Mo, W), react with MoO 2 (acac) 2 (2:1) in boiling acetonitrile in redox processes to give mixed-crystal compounds (as expected) of the approximate composition (PPh 4 ) 2 [Mo 3 O 1.9 S 8.1 ] (1) and (PPh 4 ) 2 [Mo 1.4 W 1.6 O 1.3 S 8.3 ] (2), respectively. and 2 were characterized by single crystal X-ray structure analyses. The various anions o f 1 and 2 contain {M VI (μ-S) 2 Mo IV O (μ-S ) 2 M VI } cores (M = Mo (1); Mo, W (2); bond angle M ··· Mo ··· M = 151.3° (1) 152.2 - 154.3° (2)), which have high formation tendencies. The terminal positions are occupied by S and O atoms. The trinuclear anions of 1 correspond to the type [XYMo(μ-S) 2 MoO(μ-S) 2 MoSX ] 2- (X = O, S; Y = S, S 2 ). In 2 there are two sets of anions of the type [XYM(μ-S) 2 MoO(μ-S) 2 WS 2 ] 2- and [ZSM (μ-S) 2 MoO(μ-S) 2 MZS] 2- (Z = S n /O m ) in the ratio o f 2:1, occupying two symmetry-independent sites in the unit cell. Complex 2 is the first structurally characterized mixed-metal Mo - W thiometalate.

(1) The utilization of two-dimensional (2 D) 13 C / 1 H , 31 P/ 1 H and 195 Pt/ 1 H heteronuclear shift correlations for the sign determination of various coupling constants [e.g., 2 J( 31 PPt 13 C) > 0 (trans), 2 J( 31 PPt 13 C) < 0 (cis), 3 J( 31 PPtC 13 C) > 0 (cis, trans), 4 J( 31 PPtCC 1 H ) > 0 (trans), 4 J( 31 PCC 1 H ) < 0 (cis), 3 J( 195 PtCC 1 H ) > 0, 2 J( 31 PC 1 H ) < 0, etc.] is demonstrated, using standard equipment. The complexes [trans-(Bu 3 P) 2 Pt(C ≡ C -H) 2 ] and [cis-(Et 2 PCH 2 CH 2 PEt 2 )Pt(C ≡ C - H) 2 ] (2) serve as model compounds.

Gas-phase He I and He II photoelectron spectroscopy and Pseudopotential “ab initio” calculations were used to determine the electronic structure of some 4-membered cyclic amides containing Si, Sn and Pb. The IE splitting on the non-bonding nitrogen-localized m .o .s ., n N asym (a 2 ) and n N sym (b 2 ), due to the “through space” interaction is critically affected by the planar ring molecular structure and the coordination of the silicon and tin atoms of the ring. The pseudopotential “ab initio” model resulted successful in describing the electronic structure of the molecules containing heavy atoms, at a Koopmans’ approximation level.

The crystal structure of cubic K 2 Cd(CN) 4 (a = 1286.01(9) pm, Fd 3̅ m, Z = 8) was determined from 175 independent X-ray single crystal reflections (w R = 0.0178). Regular [Cd(CN) 4 ] 2- tetrahedra (Cd - C = 222.5(3), C - N = 111.3(3) pm) and strongly trigonally elongated [KN 6 ] octahedra ( K - N = 293.0(2) pm) are arranged in a normal spinel type manner.

The complexes Ph 2 SeAuCl (green) and Ph 2 SeAuCl 3 (brown) are prepared by direct reaction between the diphenylselenide ligand and the corresponding gold chloride. The crystal structures confirm the presence of monomeric, linear (Au I ) or square planar (Au III ) coordinated complexes with bond lengths A u(I)-Se 2.378(1), Au(III)-Se 2.445(1) Å. Short non-bonded contacts Au(I) ··· Au(I) and Au(III) ··· Cl are observed.

(4). Tc 2 (CO) 10 has been photolyzed in the presence o f butadiene at - 20 °C in pentane. Under these conditions the only product which could be characterized is the complex [Tc 2 (CO) 8 ][μ-C 4 H 6 ] The X -ray structure determination shows that 1 is isomorphous with the homologues species [M 2 (CO) 8 ][μ-C 4 H 6 ] (M = Mn, Re) with the trans-butadiene ligand bridging the two technetium centers. 4 is compared to the manganese (5) and rhenium species (6 ).

x In the series with nominal stoichiometry Ba 1-x A x Pb 0,75 Bi 0,25 O 3 (A = K, Rb with = 0.1, 0.2, 0.3, and A = Cs with x = 0.1) solid solutions were prepared. The composition of the samples obtained was verified by X -ray techniques. All compounds crystallize tetragonally with a 3-dimensional array of Pb(Bi) - O 6 octahedra and Pb(Bi) -O -Pb(Bi) bonding angles of 180° (c-axis) and 165° (x K = 0.3) 168° (x Rb = 0.3 and x Cs = 0.1) within the a/b plane. Superconducting transition temperatures o f Ba 1-x A x Pb 0,75 Bi 0,25 O 3 with T e = 12 (“onset”) were determined using a SQUID magnetometer.

{K-[2 2 2]-Crypt} 2 Se 7 ·H 2 0 has been prepared by the reaction of a solution of potassium polyselenide in dimethylformamide at room temperature as black crystals, which were characterized by IR spectroscopy as well as by an X-ray structure determination. Space group P2 1 /n, Z = 4, 5055 observed unique reflexions, R = 0.103. Lattice dimensions at 20 °C: a = 1435(1), b = 1320(1), c = 2966(2) pm, β = 102.50(6)° The heptaselenide ion represents approximately part of a helical chain of polymeric selenium.

(1) The mixed terminal ligand iron-sulfur clusters [F eIL 3][Fe4S4I3L] and [Fe4S4I2L '2] (2) with the neutral ligands L = (M e2N )2CS and L' = (C4H 9N H )2CS have been synthesized by the reaction o f F eI2L2 with 1.5 equivalents o f Fe(C O )5 and 2 equivalents o f sulfur and by the reaction o f F eI2L '2 with 3 equivalents o f Fe(CO)^ and 4 equivalents o f sulfur, respectively. The crystal structures o f 1 and 2 were determined from single crystal X -ray diffraction data. 1 crystallizes in the triclinic space group P 1 with a = 968.6( 1), b = 1466.2( 1), c = 1679.1(1) pm, a = 91.51(1),/?= 93.43( 1), y = 90.82( 1)°, V = 2379.2 * 106 pm 5, Z = 2, R = 0.054. 2 crystallizes in the m onoclinic space group P2 Jn with a = 930.2(1), b = 1666.1(1), c = 2335.6(1) pm, β = 97.26°, V = 3 5 90.8 x 106 pm 3, Z = 4. R = 0.055. The anion [Fe4S4I3L] o f 1 exhibits a nearly undistorted [Fe4S4]2+ core. The F e - S distance to the thiourea ligand is found at 230.6 pm. The m ost striking feature o f the neutral cluster o f 2 is the very short F e - F e distance (268.7 pm) between the iron atom s with thiourea ligation which is possibly a consequence of back-donation. The F e - S thiourea distances in 2 were found to be 230.8 and 231.5 pm , respectively.

The following series of complexes [MLL'] n+ was prepared: M = Co, Rh, Ru, a) L, L' = η 5 -C 5 Me 5 , b) L, L ' = η 5 - C 5 Me 5 , H 2 O, c) L, L' = η 5 - C 5 Me 5 , tripod (CpCo(P(O)(OEt) 2 ) 3 - ), d) L, L' = tripod. Redox transitions o f the complexes were investigated by cyclic voltammetry. The results are discussed in terms of ligand field and ligand charge stabilization of the respective electron configurations.

Using a miniature zone melting device with focused infrared light it was possible to grow crystals of bis(dimethylamino)methylborane (1) and bis(monomethylamino)methylborane (2) at temperatures o f 182 K and 177 K, respectively. The crystal structure and the X - X difference electron density have been determined at temperatures o f 120 K (1) and 115 K (2). 1 crystallizes in the orthorhombic space group Pbca with a = 758.87(7), b = 1559.74(12) and c = 1296.73(12) pm. The mean B - N distance is 143.1(3) pm. 2 crystallizes in the monoclinic space group P2 1 /c with a = 775.06(6), b = 1533.94(17), c = 1011.06(10) pm and β = 102.669(7)° with intermolecular N ··· H hydrogen bridges. The mean B - N distance is 141.5(2) pm. It is shown that the variation of torsion angles at small angles has more influence on bond lengths than the same or a greater variation at large angles and that it is necessary to pay more attention to the torsion angles ( C - B - N - C ) rather than to the interplanar angles (plane N ,B,N - plane N ,C,C ).

o-Hydroxybiphenyl-o'-oxyacetamides and o.o'-biphenyldioxydiacetamides can be prepared from the reaction of o,o'-biphenyldiol and the appropriate chloroacetamide. The products are characterized by their solution ( 1 H , 13 C) and solid state ( 13 C) NMR spectra.

Deeply coloured 1:1 electrolytes of the type Tris(dimethylamino)cyclopropendiylium ) 2+ SeX 6 2- (X = Cl, Br) have been obtained as metastable products of a kinetically controlled redox reaction and are compared with their Tellurium counterparts. According to UV and polarographic evidence there is strong OSCT -interaction between the SOMO of the organic moiety as acceptor and the a lg *-HOMO of the ns 2 anion as donor. The a lg * donor capacity of ns 2 anions of type EIX 6 2- increases with decreasing atomic weight both of the central atom El and the ligand X. This trend and be rationalized on the basis o f a simple qualitative MO argument. Upon gentle heating the SeX 6 2- systems are oxidized by their own counter cation. The novel SeX 6 ⨪-species thus generated either disproportionates (X = Br) or acts as a selective radical halogenating agent (X = Cl) for the organic cation.

X -ray analysis of the first azo-dye stuff of 2,7-methanoaza[10]annulene is reported.

2-tert-buiyl- Three amino acid analogues of citric acid siderophores were synthesized. The synthetic strategy involved condensation of 2-tert-butyl-1,3-di(N-hydroxysuccinimidyl) or 1,3-bis(pentachlorophenyl)citrates with N-ethyl-ω-aminoalkylhydroxamates. The examination of biological properties of the obtained compounds revealed their poor, if any siderophore activity and thus confirmed the structural requirements previously suggested for siderophores of this type.

The first SF5-substituted perfluoro iodo alkene (E) - F 5 SCF = CFI was synthesized from the phosphonium salt precursor [(E)-F 5 SCF = CFPMe 3 ] + BF 4 - and iodine.

For the first time SF 5 containing organic phosphonates, SF 5 CF = CFP(O)(OR 1 ) 2 have been prepared from trimethylsilylphosphites, (R 1 O) 2 POSiMe 3 (R 1 = Et, R 1 = SiMe 3 ) and trifluorovinylsulfur pentafluoride, SF 5 CF = CF 2 in an Arbuzov type reaction.

In order to determine the effect of Al(III), Ga(III) and In(III) on the inorganic phase of bone, a model study has been undertaken, investigating a series of fluoroapatites in which part of the Ca(II) ions were substituted be these cations. Diffractometric and spectroscopic studies show that low concentrations of the incorporated metals neither affect the crystallographic characteristics nor the strength of the P - O bonds of these apatitic materials.