Volume 40, Issue 1

Ba 3 (AsS 4 ) 2 · 7H 2 O crystallizes in the monoclinic system, space group P2 1 /c (No. 14) with a = 1275.8(4) pm, b = 1282.9(4) pm, c = 1907.7(6) pm, β = 139.5( 1)°. In the structure there are isolated AsS 4 3- tetrahedra with As-S-bond lengths between 216.3 and 217.8 pm. The Ba 2+ ions are coordinated by a total of 8 to 10 S 2- ions and H 2 O molecules

The new compounds Ca 5 Ga 2 Sb 6 , Ca 5 In 2 Sb 6 and Sr 5 In 2 Sb 6 crystallize in the orthorhombic system (space group: Pbam, No. 55) with the lattice constants: Ca 5 Ga 2 Sb 6 : a = 1402.1(5) pm, b = 1210.6(4) pm, c = 445.2(2) pm; Ca 5 In 2 Sb 6 : a = 1425.6(5) pm, b = 1213.3(4) pm, c = 457.2(2) pm; Sr 5 In 2 Sb 6 : a = 1474.9(5) pm, b = 1269.6(4) pm, c = 466.0(2) pm. In the structures there are anionic E(III) 2 E(V) 6 -strings, compensated by the alkaline earth ions. The compounds belong to the Zintl phases

[VCl 3 (NSCl) 2 ] 2 , which is a chloro-bridged dimer, is formed by the reaction of VCl 4 with (NSCl) 3 . Thermal decomposition of the vanadiumtrichloride-thiazylchloride adduct, as well as the reaction of VCl 4 with (NSCl) 3 in the presence of sulfurdichloride lead to the ionic species [N(SCl) 2 ] 3 [V 2 Cl 9 ]. By the reaction of the recently reported complex (AsPh 4 ) 2 [(VCl 5 ) 2 (N 2 S 2 )] with (NSCl) 3 in CH 2 Cl 2 -solution AsPh 4 [VCl 4 (N 2 S 2 )] is prepared, which contains the anion as a polymer with N 2 S 2 -bridges. The IR spectra are reported and assigned

The syntheses and IR spectra of the complexes [Mo 2 (O 2 C-Ph) 4 X 2 ] 2⊖ with X = N 3 , CI, Br and the counter ion PPh 4 ⊕ are reported. The azido and the bromo complexes are obtained from a solution of [Mo 2 (O 2 CPh) 4 ] with PPh 4 N 3 in pyridine or by reaction with PPh 4 Br in CH 2 Br 2 , respectively. When (PPh 4 ) 2 [Mo 2 (O 2 CPh) 4 (N 3 ) 2 ] is dissolved in CH 2 Cl 2, nitrogen is evolved and the complex with X = CI is obtained. The crystal structure of (PPh 4 ) 2 [Mo 2 (O 2 CPh) 4 Cl 2 ] · 2CH 2 Cl 2 was determined from X-ray diffraction data (5676 observed independent reflexions, R = 0.042). It crystallizes in the monoclinic space group P2 1 /n with four formula units per unit cell; the lattice constants are a = 1549, b = 1400, c = 1648 pm, β = 94.6°. The centrosymmetric [Mo 2 (O 2 CPh) 4 Cl 2 ] 2⊖ ion has a rather short Mo-Mo bond of 213 pm, whereas the MoCl bonds are very long (288 pm)

The thioarsenate(III) (enH 2 ) 3 (As 3 S 6 ) 2 · 6en 1 (en = ethylenediamine) has been prepared by the reaction of ethylenediamine with As 2 S 3 and its structure established by X-ray structural analysis. 1 contains discrete cyclic As 3 S 6 3- anions with a six-membered As 3 S 3 -ring in the chair conformation. The As atoms display a ψ-tetrahedral coordination

The 31 P{ 1 H}NMR spectra for a series of pentacyanoferrates(II) of the type Na 3 [Fe(CN) 5 L] (L = phosphine or phosphite) have been measured. A low field chemical shift range of 48.1-88.7 ppm for phosphine complexes and of 32.5-48.4 ppm for phosphite complexes is observed when one compares free vs. coordinated ligands. The correlation between chemical shifts in the 31 P NMR spectra and isomeric shifts in the Mössbauer spectra is investigated and discussed

The systems GaX 3 -Ga 2 S 3 and InX 3 -In 2 S 3 (X = Cl, Br, I) are quasi-binary and contain the intermediate phases GaSX and InSX with incongruent melting behaviour. Stability regions of GaSCl and GaSBr at elevated temperatures are shifted towards the respective binary halides and include compositions Ga 9 S 8 X 11 which in an earlier work were reported as separate crystalline phases. InSCl and InSBr (CdCl 2 -type structure) also show a significant phase width towards the respective binary halides, but with the maximum melting temperature remaining at stoichiometric compositions. Cell parameters and symmetry of InSI are related to InSeI, but do not confirm the proposed isotypic relationship

Hydrolysis of CF 3-n Cl n SCl with water yields the thiosulfinates CF 3-n Cl n SS(O)CF 3-n Cl n and thiosulfonates CF 3-n Cl n SSO 2 CF 3-n Cl n as stable intermediates. They were synthesized on a preparative scale by special reactions and characterized. A new mechanism, based upon additional reactions of the isolated products, is discussed and extended to the reaction of chlorine with water

The title compound can be isolated from concentrated solutions of 4,4′,5,5′-tetramethoxy-2,2′- dithiobiphenyl (DTB, 2) and iodine as blue needles with brass-coloured luster. The crystal structure consists of stacks of (partially oxidized) DTB units with alternating orientations and of disordered polyiodide chains in channels between these stacks. The DTB molecule is not planar; the dihedral angle between the two phenyl rings is 25.1°, the dithio bridge is inclined by 41.7° to the longitudinal axis. The bond distances and angles of the disulfide group are in the normal range, the dihedral angles (C Ar SS′C Ar′ = 55.6°, C Ar C Ar SS′ = 41.3°) differ from the ideal values of ca. 90° as a consequence of the cyclic structure

Several polyhalide anions containing iodine and bromine have been synthesized with 2,2′- bipyridylium (BPH + ) as the cation. The crystal structures of three compounds have been investigated by X-ray crystal structure analyses. BPH + (H 3 O) + (IBr 2 ) 2 - (P1̄, a = 780.0(3), b = 815.4(3), c = 1547.9(6) pm, α = 75.59(7), β = 82.28(8), γ = 88.15(8)°, R = 6.5%) contains two independent, nearly linear, asymmetric IBr 2 - groups. In BPH + I 2 Br 3 - (P2 1 /c, a = 1269.1(6), b = 673.0(4), c = 2047.4(8) pm, β = 112.39(9)°, R = 6.3%), the anion is V-shaped like other pentahalide anions. It can be characterized as consisting of two IBr molecules linked to a bromide anion with the longer I-Br bonds at the central atom. The polyhalide anions in [xxx] (P2 1 /m, a = 435.1(2), b = 1710.6(7), c = 1349.0(6) pm, β = 97.56(9)°, R = 15.5%) form infinite zigzag layers. They are built up by IBr 2 - anions which are connected by iodine molecules. The cations are enclosed in columnar cavities within these layers

The crystal structure of SCl 3 + AsF 6 - is reported. The mean S-Cl stretching frequency ν̄ of the SCl 3 + cations, weighted according to the degree of degeneration, in the different SCl 3 + X - salts is directly proportional to the mean S-CI distance r̄ scl , the force constant f SCl and the sulfur. . . anion distance (Cl 3 S + . . . X - ). That SCI 3 + Cl - should be isostructural with PCl 4 - , the large variation in the S-CI stretching frequencies in the SCl 3 + X - salts is due to cation-anion interaction forces

Orthorhombic [Pd(C 2 H 8 N 2 ) 2 Br 2 ][Pd(C 2 H 8 N 2 )][ClO 4 ] 4 , C 8 H 32 Br 2 Cl 4 N 8 O 16 Pd 2 , M r = 890.42, crystallizes in space group Iba2, a = 9.651(2), b = 13.951(8), c = 10.771(2) Å, Z = 2, V = 1412.80 Å 3 , d c = 2.05 g cm -3 , R = 0.0564 for 1545 unique reflections. Data collection: MoK α , λ = 0.71069 Å, room temperature. The structure is a typical Wolffram’s Salt Analogue (WSA) with infinite stacks of planar [Pd(en) 2 ] 2+,4+ complex cations bridged by bromides. The ligands are three-dimensionally ordered. Intra-chain and inter-chain hydrogen bridges link the ligands with the perchlorate counter ions which occupy statistically two different orientations. Diffuse sheets appear together with Bragg reflections for 1 odd layers indicating a thermally activated motion of the bromides in chain direction. This model was confirmed with temperature dependent Weissenberg work

The 1:2 molecular complexes formed from 1,4-phenylenebis(dimethylphosphane) and boranes, trialkyl-aluminum and -gallium have been reduced by potassium in THF in the presence of a K + - complexing crown ether. The bis(borane) complex anion radicals proved to be quite persistent, whereas corresponding aluminum radical complexes could only be observed below 240 K. The bis(trimethylgallium) complex gave gallium metal on reduction with potassium. An ESR spectroscopic comparison with the anion radicals of the free ligand, of corresponding chalcogenides, imines and phosphonium salts demonstrates negligible effects of P-complexation on the π spin distribution but high sensitivity of the 31 P coupling constant towards coordination of electrophiles at the basic P(III) centers

Triphenylphosphene (3b), generated thermally or photochemically from 1b, undergoes olefination reaction with 4.5-benzotropone (6) to yield 1-(diphenylmethylen)-4.5-benzocycloheptatriene (9); the oxaphosphetane 7b is assumed to be the intermediate of this reaction. In an analogous way, 4-pyrone (15) is transformed into 4-(diphenylmethylen)pyrane (16). Corresponding olefination behaviour is observed in the reactions of 6 and 15 with diphenylketene. In the reaction of tetracyclone (20) with diphenylketene (3a), the olefination sequence leads to the formation of (diphenylmethylen)tetraphenylcyclopentadiene (21) via betain 22a and the cycloadduct 23a. The spirocyclic reaction product 26a probably arises from the same betain - like intermediate (22 a → 25 a → 26 a). The analogy in triphenylphosphene reactivity towards 20 is restricted to the [2+8]-cycloaddition step (formation of 26b)

Heating of the decacarbonyls M 2 (CO) 10 (M = Mn, Re) in tetrahydrothiophene under reflux gave the substitution products M 2 (CO) 9 (C 4 H 8 S) (M = Mn, Re) and Mn 2 (CO) 8 (C 4 H 8 S), respectively. In the former an equatorial CO group has been substituted, while in the latter the tetra- hydrothiophene ligand bridges symmetrically two Mn-Mn bonded Mn(CO) 4 units. The manganese compounds (monoclinic, P2 1 /c) were characterized by means of X-Ray structure analysis

The triply Mo-Mo bonded molecule [Cp(CO) 2 Mo] 2 was reacted with the cyclic sulfides S(CH 2 ) n (n = 4-6). The species Cp(CO) 2 Mo(μ-S(CH 2 ) n )Mo(CO) 2 Cp were isolated and characterized by their analytical and spectroscopic data. X-Ray structure analysis of the compound Cp(CO) 2 Mo(μ-S(CH 2 ) 6 )Mo(CO) 2 Cp proved the cyclic sulfide to act as a bridging ligand

9,9′-Oxy-bis(acridinium) salts 2a and 2b as well as the 9,9′-thio-bis(acridinium) salt 2c have been compared with other 9-substituted acridinium salts by 1 H NMR, 13 C NMR, and UV/VIS spectra. The data show that the bond state of the acridine rings in 2a-c is quite similar to that in 9-(pseudo)halide-substituted acridinium ions, i.e., the aromatic conjugation throughout the heterocyclic system is not disturbed

Water was irradiated with ultrasonic waves under an argon atmosphere which contained small amounts of carbon dioxide, nitrous oxide or methane. The yield of the products was measured as a function of the composition of the gas atmosphere. Maximum yields were observed at a few per cent of the added polyatomic gas. No chemical effects occurred in the irradiation under an atmosphere of pure CO 2 , N 2 O or CH 4 . It is concluded that the gas mixture in the tiny gas bubbles, in which the chemical effects are brought about, is not in Henry’s equilibrium with the aqueous gas solution. The main product of the sonolysis of CO 2 is CO, a small amount of formic acid also being formed. The sonolysis is explained by both the attack of H atoms from the sonolysis of water and direct decomposition of CO 2 due to the high temperatures existing in compressed gas bubbles. The main products of the sonolysis of N 2 O are nitrogen, nitrite and nitrate. N 2 O enhances the rate of various oxidations such as that of iodide, nitrite and propanol-2. In the methane containing solution, a lot of hydrogen is produced, the main oxidation products being ethane, ethylene, C 3 - and C 4 -hydrocarbons and carbon monoxide. A mechanism is postulated which involves both the attack on methane by radicals from the decomposition of water and thermal decomposition of methane. The local radical concentrations are so high that a methane molecule may undergo multiple radical attack. The similarity between sonolytic reactions and reactions occurring in flames is emphasized

Photochemical reactions of thymine linked to hypoxanthine or imidazole by a trimethylene chain were studied in aqueous solution. Irradiation (λ = 254 nm) of thymine-hypoxanthine pair yielded two internal cycloadducts with azetidine and cyclobutane part structures. Sensitization and quenching experiments suggested that the excited singlet was the reactive state in the photo-cycloaddition reactions. Only cyclobutanes were isolated from irradiated (λ = 290 nm) solutions of thymine-imidazole pairs. Photocycloadditions were reversible upon irradiation at λ = 254 nm

The thioformimidate 4, which may be obtained by S-methylation of 5 reacts with chloroacetyl chloride/triethylamine to yield the trans-2-azetidinone 7. 7 is dehalogenated to 8. Removal of the protective group leads to 9, which undergoes ring closure by the action with mercuric chloride/ mercuric oxide. Chlorolysis of 8 and the subsequent reaction with hydrofluoric acid/acetonitrile yields 12. The treatment of 12 with silver tetrafluoroborate/silver oxide gives also the title compound 10

[P(C 6 H 5 ) 4 ] 2 S 8 was prepared from Na 2 S 4 and PPh 4 Cl in ethanol solution and characterized by its IR spectrum

Besides KNaO and RbNaO, KLiO is the third example of hitherto unknown and unexpected in- teralkaline metal oxides. The X-ray investigation of the orthorhombic KLiO (Z=8) shows a new structure with separated layers of [xxx] anions in which every lithium atom is co-ordinated by a triangle of three oxygens. The compounds KTlO, RbTlO and CsTlO are already known. Now serveral new ternary alkaline oxides with monovalent thallium have been obtained. In the Na 2 O-Tl 2 O system the red compounds NaTlO and Na 3 TlO 2 were found. Further- more KTl 3 O 2 , RbTl 3 O 2 and CsTl 3 O 2 have been prepared. Their unit cells (Z=3) correlate to the unit cell of hexagonal Tl 2 O (Z=6)

Dithiooxamide 1 reacts with hexafluoroacetone 2 at room temperature to yield 1,1,1,3,3,3-hexafluoro-2-propylamino-1-thiooxamide 3 and sulfur. The modes of formation of the bis(trifluoromethyl)-methyl group from hexafluoroacetone, the migration of oxygen and the elimination of sulfur are not clear. Crystals of 3 are monoclinic, space group Cc, with a = 2865.3(13), b = 924.4(9), c = 702.9(6) pm, β = 93.3(7)°. The structure was refined to R = 0.067 from 614 reflections

The coordination of tertiary phosphinothioformamides and the isomeric S-alkyl phosphinothioformimidates to BrRe(CO) 5 gives the fac-bromotricarbonylrhenium complexes 1a, b and 2a, b with P,S-chelate ligands. Unlike the analogous manganese complexes, the NMR spectra of dissolved 1b and 2a, b show a splitting of the N-alkyl ( 1 H, 13 C) and phosphorus signals indicating E/Z isomerisation of the ligands

A novel synthesis of thiophene and furan β-enaminoamides via the reaction of halomethyl acet-p-toluidide with isothiocyanates and isocyanates were reported