Volume 53, Issue 11

9-Trimethylsilyl- and 9-trimethylgermyl substituted derivatives of 1-(9-fluorenyl)germatranes C 13 H 8 (R)Ge(OCH 2 CH 2 ) 3 N (1 - 3) (1: R = H; 2: R = Me 3 Si; 3: R = Me 3 Ge) were prepared by the reaction of 9-tribromogermyl derivatives of fluorene C 13 H 8 (R)GeBr 3 (4 - 6) with N(CH 2 CH 2 OSnAlk 3 ) 3 (7: Alk = Et; 8: Alk = Bu). 1-(9-Trimethylstannyl- 9-fluorenyl)germatrane (14) was synthesised by the reaction o f the germatrane (1) with Me 3 SnNMe 2 . Formulas and structures were established by elemental analyses, ( 1 H, 13 C) NMR spectroscopy and mass spectrometry; crystal structures of 2 and 14 are reported.

The reaction between Br 3 GeAll (1) and N(CH 2 CHMeOSnBu 3 ) 3 (2, mixture of isomers) yielded N(CH 2 CHMeO) 3 GeAll (3) as a mixture of diastereomers. Three azagermatranes of the type N(CH 2 CH 2 NR) 3 GeAll (9, R = H; 10, R = Me; 11, R = Me 3 Si) have been synthesized from the reaction of (Me 2 N) 3 GeAll (5) with N (CH 2 CH 2 NHR) 3 (R = H, 6; Me, 7; Me 3 Si, 8). Composition and structures of the new compounds were established by elemental analyses, 1 H and 13 C NMR spectroscopy and mass spectrometry.

Reaction of (Et 4 N)Cl with AS 2 S 3 and Na 2 S in acetonitrile at 110°C affords the polymeric thioarsenate(III) (Et 4 N) 2 As 6 S 10 in which the cyclic [As 3 S 6 ] 3- and chainlike [As 3 S 7 ] 5- trinuclear molecular building units are linked together through common sulphur atoms into infinite double chains. In contrast, reaction of the same starting materials at higher temperatures (180°C) in water leads to formation of a markedly denser phase (Et 4 N) 2 As 8 S 13 , whose thioarsenate(III) 1 ∞ [As 8 S 13 2- ] anions exhibit a higher condensation grade. These likewise double chains are composed of cyclic [AS 3 S 6 ] 3- and dinuclear [As 2 S s ] 4- units with shared ѱ-AsS 3 tetrahedra corners. Analogous treatment of (Et 4 N)Cl with As 2 Se 3 and Na 2 Se in acetonitrile (T =110°C) yields (Et 4 N)[SeAsSe 7 ].

Treatment of triphenylmethyldichlorophosphine 1 with aluminium trichloride in the presence of tert-buty1 chloride leads, after hydrolysis, with high selectivity to di-tert-butylphosphinic chloride 5. The reaction is suggested to proceed via a chlorophosphinidene intermediate which is trapped by the alkyl chloride.

The arene ligand exchange mechanism of slipped arene triple deckers [Bis{(η 5 -Cp R )Co}-μ-{η 4 :η 4 -arene}] (R = Me 5 , 1,2,4 tri-tert butyl, arene = benzene, toluene) 1 was studied by 1 H-NMR spectroscopy for different concentrations and solvents. It has been found that triple deckers of type 1 decompose slowly in solution. A unique equilibrium, between these triple deckers and the mixed sandwich complexes [(η 6 -arene)Co(η 5 -Cp R )] and 14 e [(η 5 -Cp)Co] solv fragments generated in situ by decomposition o f 1 exists. In addition to this equilibrium arene lability of the thus formed mixed sandwich complex type has been detected by NMR making slipped triple deckers 1 ideal single source compounds for the generation of two [(η 5 -Cp)Co] fragments in one reaction step. Such fragments are valuable metal ligand components with high synthetic utility in organometallic chemistry.

Bis[2-phenyl-,2-dicarba-closo-dodecaboran-1-yl(12)]phenylphosphine (2) was obtained in 91% yield from phenyldichlorophosphine and two equivalents of 1-lithium-2-phenyl-1 ,2- dicarba-closo-dodecaborane(12) in ether and characterized by spectroscopy ( 31 P, 11 B, 1 H, 13 C NMR; IR) and by X-ray structure determination.

A new procedure is described for the synthesis of α,β-glycosyl cyanides by the reaction of per-O-benzylated S-α-ᴅ-glycopyranosyl phosphorothioates with trimethylsilyl cyanide in the presence of Lewis acid. Starting S-glycosyl phosphorothioates are prepared, directly, from O-benzyl protected reducing D-hexopyranoses (gluco-, galacto-, manno-) and alkylammonium salt of phosphorothioic acid under Lewis acid catalysis.

[LCu{μ-(OH) 2 (C 2 O 2 )}CuL](ClO 4 ) 2 , (HL = N,N-dimethyl N-propylsalicylald-imine) was synthesised and its crystal structure was determined. C 26 H 36 CI 2 Cu 2 N 4 O 14 , triclinic space group P1̅ with a = 9.288(9), b = 10.016(11), c = 10.09(2) Å and a = 101.05(11), β = 108.22(10), γ = 110.22(10)°, V = 787(2) Å 3 , Z = 2. Two copper(II) ions in a distorted square-planar coordination are bridged by an oxalic acid molecule to form dinuclear units. The copper(II) centres are separated by 5.2 Å and antiferromagnetically coupled (J = -478 cm -1 ), which follows from temperature-dependent magnetic susceptibility measurements in the range 12 to 300 K.

Condensation of the bis(trimethylsilyl)ylide Ph 3 PC(SiMe 3 ) 2 with PX 3 (X = Cl, Br) yields the ionic tetramers 4a,b of ylidediyl-halophosphanes. Their cations (Ph 3 PC) 4 P 4 X 3 + possess a tetraphosphabicyclo[2.2.2]octane (or tetraphospha-barrelane) skeleton ([AC] 3 BD spin system in 31 P NMR spectra). Reaction of 4a with AlCl 3 or GaCl 3 converts the singly charged cation into the tetracation (Ph 3 PC) 4 P 4 4+ having a cubane structure ([AB] 4 spin system in the 31 P NMR spectum). SbCl 5 oxidizes 4a to give the dication (Ph 3 PC) 4 P 4 Cl 4 2+ (counter ion: SbCl 5 2- ) with the barrelane skeleton either preserved (7) or rearranged into a tetraphospha-bicylco[3.3.0]- octane structure 8. In the latter case the dication contains a central diphosphanedionium bridge. Replacement of a chloro-substituent in 4a by an amino group also gives rise to a further dissociation and a concomitant rearrangement. The resulting dications (Ph 3 PC) 4 P 4 NR 2 Cl 2+ possess a tetraphospha-bicyclo-[3.2.1]octane structure (with eight nonequivalent phosphorus atoms).

The composition of aqueous fluoroberyllate solutions has been studied by 9 Be and 19 F NMR spectroscopy for various ratios of the beryllium and fluorine concentrations, and at different pH values. The equilibrium constants have been determined for the ligand exchange processes, which involve the species [Be(OH 2 ) 4 ] 2+ , [BeF(OH 2 ) 3 ] + , [BeF 2 (OH 2 ) 2 ], [BeF 3 (OH 2 )] - , and [BeF 4 ] 2- . These equilibria are shifted towards [BeF 4 ] 2- at high pH. No polynuclear fluoroberyllates have been detected. The fluoride exchange between the individual species is slow on the NMR time scale at room temperature, and separate sharp signals with the expected multiplicity are therefore recorded. Calculated 9 Be chemical shifts are in good agreement with experimental data.

Z-1,2-Bis(diphenylphosphino)ethene, cis-Ph 2 PCH=CHPPh 2 , forms 1:2 adducts with GaBr 3 and GaI 3 , the former of which has been identified in an X-ray diffraction study as the complex of the isomerized ligand, E-Ph 2 PCH=CHPPh 2 . The GaI 3 complex is believed to be analogous on the basis of analytical and spectroscopic data. InBr 3 affords a 1 :1 complex with an ionic structure [(Ph 2 PCH=CHPPh 2 ) 2 lnBr 2 ] + [InBr 4 ] - in which the cation contains the original cis-ligand. With Inl 3 also a 1:1 adduct is obtained, where the metal triiodide unit is attached to only one phosphorus atom of the non-isomerized (cis) ligand in the solid state. There is rapid site exchange of the Inl 3 unit in chloroform solution as followed by NMR spectroscopy. - The metal halide induced Z/E isomerization of Ph 2 PCH=CHPPh 2 has been studied in various solvents and at variable temperature with stoichiometric and catalytic amounts of AIX 3 and GaX 3 Lewis-acids. InX 3 compounds proved ineffective (X = Cl, Br, I). Anhydrous AlBr 3 was found to be most efficient, giving a 90% Z/E conversion in 10 min at 100°C in toluene. A mechanism is proposed which is compatible with the experimental data.

2-Diphenylphosphino-phenol was chosen as an ambivalent (hard/soft) chelating ligand for biologically important first row transition metals. The expected mode of complexation is relevant to trapping of metal ions in humic acids and related environmental ion exchange systems with phenolate functions. The 1:2 complex with nickel(II) is known to have a standard mononuclear square-planar structure, and experimental evidence suggests that the new cobalt(II) complex is analogous. By contrast, zinc and cadmium were found to give novel trinulear complexes [M 3 (2- Ph 2 P-C 6 H 4 O) 6 ], M = Zn, Cd. In a chain of three metal atoms, the octahedrally coordinated central atom resides on a center of inversion and is solely oxygen-bound [MO 6 ], while the two peripheral metal atoms are in a mixed coordination environment [fac-MO 3 P 3 ], The analogous manganese(II) complex crystallizes as a net trihydrate, where two different trinuclear units are present in the lattice. One is of a new type and represents a centrosymmetrical hexahydrate [Mn 3 (2-Ph 2 P-C 6 H 4 0) 6 (OH 2 ) 6 ]. The central part is an octahedral [Mn(OH 2 ) 6 ] 2+ dication, which is hydrogen-bonded to two [Mn(2 -Ph 2 P-C 6 H 4 O) 3 ] - anions. The nickel(II) complex was found to form 1:1 adducts with ZnCl 2 or ZnBr 2 . The two complexes are isomorphous. In the adduct structure the zinc atom is attached to the two oxygen atoms of the nickel compound leaving the remainder of the molecular geometry largely unchanged. Together with the two halogen atoms a tetrahedral environment [ZnO 2 X 2 ] is formed (X = Cl, Br), while the nickel atom retains its square planar [NiO 2 P 2 ] environment.

Hydrolysis of gallium tribromide complexes of 1,2-bis(diphenylphosphino)benzene in toluene solvent affords crystals of the mono-phosphonium salt [ 1,2 -Ph 2 P-(C 6 H 4 )-PPh 2 H] + [GaBr 4 ] - . The structure analysis by single crystal X-ray diffraction allows an internal comparison of Ph 2 P phosphino and Pf 2 PH + phosphonium functions.

The title compounds are prepared by slow evaporation of dilute solutions of the components. 2,3,7,8-Tetrakis(methylthio)thianthrene and -selenanthrene give isostructural 2:1 complexes with 7,7,8,8-tetracyanoquinodimethane (TCNQ) built up by donor/acceptor/donor units in which the TCNQ molecule is inserted into the cavity formed by two of the folded, oppositely arranged chalcogenanthrene molecules. These units are connected to chains by S -S contacts via the methylthio groups. From 2,3,7,8-tetrakis(methylthio)thianthrene and tetracyanoethene again a 2:1 complex is obtained, however, with a columnar structure in which two donor stacks are slightly interlinked by an acceptor stack thus forming a structure with alternating donor and acceptor molecules. The molecules are arranged in such a way that an optimum overlap of the HOMOs of the donors and the LUMOs of the acceptors, all of which are of π-type character according to MNDO calculations, is secured.

The crystal structure of the room-temperature ferroelectric phase of pyridinium periodate [C 6 H 5 NH] + [IO 4 ] - has been determined by X-ray diffraction as orthorhombic, space group Cmc2 i with a = 8.347(2), b = 7.270(2), c = 12.732(3) Å and Z = 4. It was refined to R1 =0.0281 wR2 = 0.0762 for 389 absorption-corrected reflections. The structure comprises isolated IO 4 tetrahedra linked together by disordered pyridinium cations involved in a network of bifurcated hydrogen bonds. The average I-O distance is found to be 1.75(1) Å.

By reaction of [B 6 H 6 ] 2- with (PPh 3 ) 3 AgCl in dichloromethane the belt-shaped hypho-hexaborane adduct [(PPh 3 ) 2 B 6 H 10 ] is formed. The crystal structure of [(PPh 3 ) 2 B 6 H 10 ]·CH 2 Cl 2 has been determined by single crystal X-ray diffraction analysis: orthorhombic, space group Pbnb with a = 9.804(3), b = 17.864(4), c = 21.334(2) Å, Z = 4.

The crystal structures of cis-(n-Bu 4 N) 2 [ReCl 4 (NCS) 2 ] (triclinic, space group P1̅, a = 11,245( 1), b = 20.174(3), c = 21.320(8) Å, a =109.06(2), β = 96.46(2), γ = 98.22(5)°, Z = 4) and cis-(Ph 4 P) 2 [ReCl 4 (NCSe) 2 ]·2CH 2 Cl 2 (triclinic, space group P1̅, a = 10.341(2), b = 13.436(3), c = 19.616(4) Å, α = 92.70(2), β = 92.02(2), γ = 89.99( 1)°, Z= 2) have been determined by single crystal X-ray diffraction analysis. Both ambidentate ligands NCS and NCSe are bonded via the N atom. Using the molecular parameters of the X-ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu 4 N) salts have been assigned by normal coordinate analysis based on a modified valence force field. The valence force constants f d (ReN) are 1,78(NCS) and 1,79(NCSe) mdyn/ Å.

By reaction of K 3 [Os(NCS) 3 (SCN) 3 ] with pyridine and glycerine the complex mer- [Os(NCS) 3 Py 3 ] is formed. The X-ray structure determination on a single crystal (monoclinic, space group C2/c, a = 18.6156(12), b = 15.9448(7), c = 19.555(2) Å, β = 94.657(7)°, Z = 8) reveals that the nearly linear thiocyanate groups are exclusively bonded via the N atoms with Os-N-C angles ranging from 169.9° to 177.7°.

The treatment of K 2 [OsO 2 (OH) 4 ] with oxamide in aqueous solution yields [OsO 2 (N 2 H 2 C 2 O 2 ) 2 ] 2- . The crystal structure of trans-(Ph 4 P) 2 [ OsO 2 (N 2 H 2 C 2 O 2 ) 2 ]·CH 2 Cl 2 (triclinic, space group P1̅, a = 10.447(1), b = 14.102(4), c = 16.962(2) Å, a = 90.037(1), β = 90.633(7), γ = 98.812(2)°, Z = 2) has been determined by single crystal X-ray diffraction analysis. The IR and Raman spectra were measured at room temperature. Based on the molecular parameters of the X-ray determination a normal coordinate analysis has been performed and the vibrations are assigned. The valence force constants are f d (Os=O) = 6.7, f d (Os-N) = 2.4, f d (C-N) = 4.9, f d (C=0) = 11.15 and f d (C-C) = 4.7 mdyn/Å.

The thermodynamical data of solid and gaseous aluminium neodymium chloride have been obtained by determination of the decomposition equilibria (of solid) from total pressure measurements and chemical transport reactions (gaseous). The melting diagram was determined by DTA. The enthalpy of formation of the solid phase was calculated from their heats of solution and from the enthalpies of formation and the heats of solution of NdCl 3 and AlCl 3 . Data by total pressure measurement: ΔH° B |(NdAl 3 Cl 12,f,298 ) = -749,6 ± 2,5 kcal/mol; S°(NdAl 3 Cl 12,f,298 ) = 118,2 ± 3,0 cal/K·mol. Data by solution calorimetry: ΔH° B (NdAl 3 Cl 12,f,298 ) = -748,6 ± 1,3 kcal/mol. Data by chemical transport: ΔH° B (NdAl 3 Cl 12,g,298 ) = -701,5 ± 3,0 kcal/mol; S°(NdAl 3 Cl 12,g,298 ) = 215,0 ± 4,0 cal/K-mol.

The heterogeneous reactions: OsO 4,s =OsO 4,g , 2OsO 2,s = Os s + OsO 4,g , Os s + 3OsO 4,g = 4OsO 3,g , OsO 2,s + OsO 4,g = 2OsO 3,g and the homogeneous reaction OsO 4,g = OsO 3,g + 1 / 2 O 2,g were determined by total pressure measurements. From this and from chemical transport reactions of OsO 2 and Os with Osmium tetroxide, the enthalpy of formation of gaseous OsO 3 was computed to ΔH° B (OsO 3,g,298 ) = -40,0 ± 3 kcal/mol.

The structure of the title complex consists of [Ir 3 (C 5 Me 5 ) 3 (L-prolinate) 3 ] 3+ complex cations and CF 3 SO 3 - anions. Each iridium atom is coordinated in a distorted tetrahedral manner by one cyclopentadienyl group, two carboxylate O atoms and the prolinate N atom. The iridium atoms are bridged by the carboxylate groups. Each of the three stereogenic iridium atoms has the same (S) configuration, i. e. the trimerization of the [Ir(C 5 Me 5 )(L-prolinate)] + fragment occurs with chiral self recognition.

The 2-Aminobenzylalcohols la - c produced with mercury-edta dehydrogenation the lactams 6a - c; the pipecoline 2b yielded the benzoxazine 3b indicating the participation of the nucleophilic hydroxymethyl group. The 2-aminobenzaldehydes showed a different behaviour in dependence on the ring size of the amine part: 7a, b led - via intermediate reaction of the hemiaminal 9 with the electrophilic formyl function - to the lactams 11a, b, while 7c gave rise to the aminoaldehyde 12 as major product and similarly the pipecoline 15 to the aminoketone 16. From 2′-(4-morpholinyl)-acetophenone (22) were received the lactam 31 and the aminoethanol 32, both by a twofold dehydrogenation.

The syntheses of N-alkylated derivatives of the arenethiol 4-tert-butyl-2,6-(diaminomethyl)- thiophenol and their coordination properties are reported. Compounds 4-tert-butyl-2,6-di(N-isopropyl- aminomethyl)thiophenol (3) and 4-tert-butyl-2-(N-isopropyl-aminomethyl)-6-hydroxymethylthiophenol (6 ) react with Ni(II) salts to give compounds of composition [Ni(3) 2 ]·2HCl (7) and [Ni(6) 2 ] (8). The solid- and solution-state structures of both complexes consist of mononuclear complexes with four-coordinate nickel(II) ions in approximately planar trans- N 2 S 2 coordination environments. In contrast to the parent arenethiol 4a, the sterically more encumbered ligands do not form dinuclear complexes.

Tris(dimethylstibino)amine N(SbMe 2 ) 3 is formed during reactions of sodium dimethylstibide with haloalkanes in liquid ammonia. It forms colourless monoclinic crystals, a = 12.108(1), b = 6.663(1), c = 16.891(2) Å, β = 10 1 .1 2 (1)°, P2 1 /c, Z = 4, at -78 °C. The lattice contains independent molecules with a planar NSb 3 core (sum of the angles at nitrogen 359.9°) and approximate C 3h symmetry.