Volume 35, Issue 6

Cesium silver gold(III) chloride has been prepared from hydrochloric acid solutions. The composition of the preparations is variable and depends on the ratio [Au(III)]/[Ag(I)] in solution. It corresponds to the formula Cs 2 Ag 1-x Au 1+x/3 Cl 6 . In the range 0 ≤ x ≤ 0,64 six crystallographically different phases have been observed. Above x = 0,42 a cubic phase is obtained. The stoichiometric compound Cs 2 AgAuCl 6 is obtained only from solutions with [Au(III)]/[Ag(I)] < 1. Reports in the literature which claim the stoichiometric compound Cs 2 AgAuCl 6 to exist in a cubic and in a tetragonal form cannot be confirmed. Cs 2 AgAuCl 6 crystallizes orthorhombically with the lattice constants a = 15,21 Å, b = 15,16 Å and c = 10,32 Å (Z = 8).

The synthesis of N(SCl) 2 + MF 6 - (M = As, Sb) is reported, the structure of N(SCl) 2 + AlCL 4 - is determined and some of the spectroscopic properties of the N(SCl) 2 + cation are discussed.

The cationic dicarbonyl complexes [Rh(CO) 2 (R 2 PCH 2 ) 3 CRʹ]PF 6 (R = C 6 H 5 ; Rʹ = CH 3 , -CH 2 PR 2 ), formed by high pressure synthesis from RhCl 3 (H 2 O) 3 , CO and (R 2 PCH 2 ) 3 CRʹ react with liquid ammonia at 20 °C to give the carbamoyl complexes Rh(CO)(CONH 2 )(R 2 PCH 2 ) 3 CRʹ. At 100 °C in liquid ammonia the carbamoyl-carbonyl complexes Rh(CO)(CONH 2 )(R 2 PCH 2 ) 3 CRʹ form the CO-bridged, dinuclear compounds (μ-CO) 2 [Rh(R 2 PCH 2 ) 3 CRʹ] 2 . Upon treatment of Rh(CO)(CONH 2 )(R 2 PCH 2 ) 3 CRʹ with CH 3 OH the carbomethoxo carbonyl complexes Rh(CO)(COOCH 3 )(R 2 PCH 2 ) 3 CRʹ are obtained. The new compounds were characterised, as far as possible, by their IR, Raman and 31 P NMR spectra.

BaV 10 O 15 was prepared by high temperature reaction of BaO and V 2 O 3 in H 2 -atmosphere (T > 1800°). X-ray investigations of single crystals show a new structure type with octa-hedral coordination of V 3+ /V 2+ (statistical distribution) and cuboctahedral surrounding of Ba 2+ . Orthorhombic symmetry, space group D 18 2h -Ccmb, a = 995,8; b = 1161,8; c = 941,0; Z = 4.

Ba 2 ZnGe 2 S 6 O was prepared for the first time and the crystal structure determined by using single crystal X-ray methods. The space group is D 3 2d -P4̄2 1 m, tetragonal (No. 113). Lattice constants: a = 963.59 ± 0.22; c = 645.06 ± 0.25 pm. The tetrahedral framework structure is described and discussed. Zn is linked only to sulfur. The oxygen belongs to the coordination sphere of Ge and Ba.

The electronic and resonance Raman spectra of new mixed-valence compounds of the type M 2 ʹ[M(L)X 3 ][M(L)X 5 ], where Mʹ = K, NH 4 , M = Pt or Pd, L = NH 3 or pyridine, and X = Cl, Br or I, have been studied. The single-crystal polarized reflectance spectra indicate the one-dimensional semiconductor behaviour. The polarized resonance Raman spectra confirm the --M(II)--X-M(IV)-X linear chain structure, which is in accordance with the X-ray results. The polarization of M-N bands can be explained by the Snyder's theory (1971).

The novel doubly bridged μ-methylene iron complexes μ-[C(H)CO 2 R]-μ-CO[(η 5 -C 5 H 5 )Fe(CO)] 2 (R = C 2 H 5 : 3a; R = t C 4 H 9 : 3b) have been synthesized by low-temperature photolysis of the corresponding alkyldiazoacetates 2a and 2b, resp., in the presence of [(η 5 -C 5 H 5 )Fe(CO) 2 ] 2 (1) and characterized by means of their analytical data and IR, 1 H NMR and mass spectroscopy. The geometry of 3b has been established by single crystal X-ray diffraction techniques. δ-Alkyl iron complexes of the type (η 5 -C 5 H 5 )Fe(CO) 2 [CHRRʹ] are accessible from the corresponding diazoalkanes N 2 = CRRʹ.

The Compounds [(PMe 3 ) 2 RhCl] 2 and [Rh(PMe 3 ) 4 ]Cl react with indenyllithium to give C 9 H 7 Rh(PMe 3 ) 2 . The strong Lewis basicity of this complex is demonstrated by its reactions with NH 4 PF 6 , MeI and MeCOCl which lead to the cations [C 9 H 7 RhR(PMe 3 ) 2 ] + (R = H, Me, COMe). The hydrido complex [C 9 H 7 RhH(PMe 3 ) 2 ]PF 6 reacts with 1,5-C 8 H 12 , CO and PMe 3 by complete displacement of indene to give [Rh(PMe 3 ) 2 (C 8 H 12 )]PF 6 , [Rh(PMe 3 ) 2 (CO) 3 ]PF 6 and [Rh(PMe 3 ) 4 ]PF 6 . Reaction of [C 9 H 7 RhH(PMe 3 ) 2 ]PF 6 with C 2 H 4 yields an equilibrium mixture containing the cationic tris(ethylene) complex [Rh(PMe 3 ) 2 (C 2 H 4 ) 3 ] + .

Mo(CO) 5 L complexes (L = R 2 EER 2 ʹ , R 2 EEʹR; R, Rʹ = CH 3 and/or CF 3 ; E = P, As; Eʹ = S, Se, Te) have been prepared by reaction of Mo(CO) 5 THF with L at room temperature. The new compounds were characterized by analytical and spectroscopic (IR, NMR, MS) methods.

119 Sn NMR data of a number of base-stabilized stannylenes L (L = R 3 P-SnCl 2 , (THF) x SnCl 2 , (THF) x SnBr 2 are compared with those of the corresponding tin ylid complexes M(CO) 5 L (M = Cr, W). 119 Sn NMR coordination shifts are strongly dependent on the transition metal. Increasing the number of base ligands attached to transition metal-coordinated tin(II) leads to significant upfield shifts and to increasing coupling constants 1 J( 119 Sn 183 W).

New ternary arsenides ET 2 AS 2 (E = Ca, Sr, Ba; T = Cr, Fe, Co, Ni, Cu) were prepared. The cell data were determined by X-ray powder methods. All these compounds crystallize in the tetragonal ThCr 2 Si 2 structure (I 4/mmm), which consists of layers of edge-shared TAS 4 tetrahedra. The alkaline-earth atoms are intercalated between the layers.

The Polarographie behavior of the nitrophenols in the pH range 1-13 and the influence of campher on the polarographic curves are studied. The pH dependence of the half wave potentials and the different reduction of the depolarizers in their molecular or anionic form are discussed.

The reaction of BiCl 3 , N,Nʹ-bis(trimethylsilyl)urea and acetone yields compound 1 with the formula C 22 H 46 Cl 9 N 8 O 7 Bi. After treatment of 1 with acetone/dimethylformamid the spirocompound 4,4,10,10-tetramethylspiro[5,5]-1,3,7,9-tetrazaundecadion-2,8 (3) could be isolated. The structure of 3 is described and a reaction mechanismus is proposed.

Reinvestigation of the behaviour of benzal-anils (1) towards the action of potassium cyanide was found to give a mixture of 4-imidazolidinone (6) and 4-imidazolone (7). 6 was also obtained by benzaldehyde addition to α-arylamino-α-phenylacetonitrile (7) or by condensation of benzaldehyde with α-phenylamino-α-phenylacetamide (8). The partial conversion of 6 and 7 to each other was discussed.

Some new mixed ligand tetrakis chelates derived from tris acetylacetonates of La, Ce, Pr, Nd, and Gd with other β-diketones, like 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 and 1-phenyl-3-methyl-4-acetyl-pyrazolone-5 have been synthesised. The compounds are characterised by elemental analyses and IR data. The UV spectral properties and the conductance in DMF have also been reported.

Complexes of type L n M(η 2 - pentamethylenediazirine)MʹL m , L n M/MʹL m = (CO) 5 Cr/Mo(CO) 5 , (CO) 5 Cr/Fe(CO) 4 , (CO) 5 W/Fe(CO) 4 and (CO) 5 Cr/Mn(CO) 2 5 η(-MeC 5 H 4 ) were prepared from [MʹL m (THF)] or Fe 2 (CO) 9 and (η 1 -pentamethylenediazirine)ML n . The structure of the Cr/Mo complex was determined by X-ray analysis. The IR and UV-VIS data resemble those of the corresponding homodi-metal complexes.

The 3-spiro-3ʹ,3ʹ-dimethyl-2ʹ-oxiranes of 5-benzylidene-2,4-dioxo-pyrrolidone, 5-benzyl-idene-2,4-dioxotetrahydrofuranone and 5-benzylidene-2,4-dioxotetrahydrothiophene yield the corresponding heterocyclic reductones (3 a-c) upon treatment with sulfuric acid. The tetramic acid reducton 3a can also be obtained by hydrolysis of the diazoniumsalt 5.

Nonenzymatic catalysis by bivalent ions of Be, Mg, Ca, Zn, Mn, Ni and Co and bioorganic phosphates of the formation of hydroxamic acids from acetate or amino acids has been studied systematically. Increased yields of hydroxamate were observed at particular combinations of reactants. The most prominent increase (ca. 15-fold) was found with acetate and Ni ++ , and with a combination of ATP and Be ++ . Among others especially ribose-5-phosphate and glucose-5-phosphate enhanced yields in the presence of most metal ions. Since no release of inorganic phosphate was observed, this effect cannot be interpreted as an evidence for intermediate transhosphorylation reactions; it may also result from simple catalytic effects of metal sugar complexes.

The quantum yield of singlet oxygen production was investigated in dodecylammonium propionate reversed micellar solutions containing 1,3-diphenylisobenzofuran and fluo-rescein as photosensitizer. The quantum yield was highly enhanced by the binding of fluorescein to reversed micelles, and increased with decreasing the solubilized water content in reversed micelles. Results obtained was discussed with the optical properties of fluorescein (absorption, fluorescence and phosphorescence) in reversed micellar solutions.

The optical properties (absorption and fluorescence) of fluorescein sodium were investi-gated with changing the bulk pH value in aqueous, water-methanol mixed and dodecyl-ammonium propionate reversed micellar solutions. A strong buffer action was found in the reversed micellar solutions. The pK a values for the equilibrium between fluorescein mono-and di-anions in the ground and excited singlet states highly decreased in the reversed micellar solutions compared with those in non-micellar solutions. The micellar buffer action strongly affected the initial rate of the 1,3-diphenylisobenzofuran oxidation caused by the photosensitization of fluorescein. The buffer action was closely related to the solubilized water content.

The solubilization of methylene blue in dodecylammonium propionate reversed micelles in cyclohexane depended strongly on the solubilized water content. Methylene blue solubilized in the micelle of which head groups are not completely hydrated by bound water exhibited the new absorption bands at 495 and 270 nm, but these bands did not appear in the micelle containing free water. This dye had the absorption bands at 655 and 290 nm in the latter micelle. The solubilizing process and solubilized state of methylene blue in the reversed micelles were discussed with results obtained.

A new route to synthesis of pyrrolo(2,3-b)quinolines is described based on the use of 2-chloro-3-vinylquinolines as well as 2-chloro-3-(1ʹ,2ʹ-dibromoethyl)quinolines.

4,4-Bis(trifluoromethyl)-1,3-diazabuta-1,3-dienes below 0 °C react with P(III) compounds to give 2,2-dihydro-1,4,2-diazaphosphol-4-enes. IR, 1 H, 19 F, 31 P NMR, and mass spectra data of the new heterocyclic compounds are discussed.

The cis-trans ratio of the stilbenes formed in Wittig reactions of semistabilised ylides (derived from benzyltri(hetero)arylphosphonium salts in ethanolic ethoxide) with benz-aldehyde decreases markedly in the series 2-furyl >2-thienyl >phenyl > 1-methylpyrrol-2-yl. The 2-furyl group favours a greater proportion of the cis-isomer than m-trifiuoro-methylphenyl, whereas the 1-methylpyrrol-2-yl group favours a greater proportion of the trans isomer than p-methoxyphenyl. Similarly, in Wittig reactions of carbonyl-stabilised ylides with benzaldehyde and acetaldehyde, the presence at phosphorus of 2-furyl groups results in a significant increase in the proportion of the cis-alkene compared to that formed from the related triphenylphosphonium ylide. These results are discussed in terms of both betaine and cycloaddition mechanisms for the Wittig reaction. Also discussed is their relevance to recent proposals concerning the elimination of alkene from the intermediate oxaphosphetan.

A sensitive and reproducible method for quantitative evaluation of the relative reactivities of alkylating agents was developed, based on competitve alkylation. The method is superior to the known colorimetric methods. The reactivities of the agents could also be correlated with the 13 C chemical shifts of the α-methylene. The method was successfully applied for the ranking of "soft" alkylating agents of low reactivity.

Keywords Two known furanoid diterpenes Teucrin A (1) and Teucrin E (2) were isolated from the bitter fraction of the aerial parts of Teucrium chamaedrys L. Besides these two compounds, Teuchamaedryn A (3) and B (4) were isolated from the better fraction as well. The structure and the stereochemistry of Teuchamaedryn A, B and Teucrin E were established on the basis of spectral evidence, chemical transformation and correlation.

Trimethylsiloxyalkanols and their tributyltin(IV) derivatives have been synthesized and the nature of the species present in solution has been discussed on the basis of spectral data.

Two lead antimony phosphates have been prepared, which both crystallize with the cubic eulytine structure. Pb 3 Sb III (PO 4 ) 3 has the lattice constant a= 1037.2 pm and Pb 11 Sb V (PO 4 ) 9 has a = 1037.5 pm. The X-ray diffraction diagrams appear nearly identical. In their chemical and thermal behaviour these compounds differ in a characteristic manner, however. The relatively large cell volume of Pb 3 Sb(PO 4 ) 3 is attributed to the very distinct stereochemical activity of the lone electron pair of Sb 3+ .

Monomeric Bis(dimethylgallium)N,Nʹdimethyldithiooxamide has been prepared by the reaction of Ga(CH 3 ) 3 and [HN(CH 3 )C(=S)-] 2 in a 2:1 molar ratio. Two configurational isomers are formed and according to the 1 H NMR and vibrational spectra both forms of these molecule consist of two fused five-membered rings, with an almost planar structure. The preliminary results of the X-ray structure determination are given.

BaTiS 3 , black single crystals, (a = 675.6(1), c = 579.8(1) pm, Z = 2, space group P6 3 /mmc, 4-circle-diffractometer 1° ≤ θ ≤ 24°, AgKa, R=3.1%) is isotypic with BaNiO 3 , BaVS 3 , BaTaS 3 .

The title compound is prepared by treating ReNCL with excess POCl 3 . The complex is isotypic with the corresponding tungsten complex [WNCl 3 · POCl 3 ] 4 · 2 POCl 3 . The structure consists of Re 4 N 4 eight-membered rings with alternating Re ≡ N-Re bonds. The IR spectrum was recorded and assigned.

Four ternary sodium phases with the formula Na 2 BX (B = Cd, Hg; X = Sn, Pb) were prepared and structurally investigated. The structures of the cubic phases Na 2 HgSn, Na 2 CdPb and Na 2 HgPb (space group F4̄3m) are closely related to Li 3 Bi, that of Na 2 CdSn (space group P 6 3 mmc) to the hexagonal structure of Na 3 As.

The presence of small amounts of copper in galena-electrolyte systems leads to similar effects as those which can be ascribed to variations in the bulk electronic properties of semiconducting minerals. It is shown how trace amounts of copper can influence reproducibly the dissolution rate, the electrical polarizability and the rest potential of galena.

Hexaziridinocyclotriphosphazene forms a 2:1 clathrate with benzene. The benzene makes a sandwich between the two phosphazene molecules with the planes of the rings parallel. The geminal aziridinyl groups have a most unusual eclipsed conformation.

Hydride abstraction by trityl tetrafluoborate from a mixture of cyeloheptatriene[1,2]-and cycloheptatriene[3,4]-p-dithiine gave tropenylium[1,2]-p-dithiin tetrafluoborate. The latter was found to add either methoxide or various thiolates only at the tropenylium C-3, which constitutes the first entry to regiospecifically trifunctionalized cycloheptatrienes. In contrast, cycloheptatriene[1,7]-p-dithiine or various other cycloheptatrienes substituted at C-7 with either methylthio or t-butylthio groups were found to undergo alkylthiolate abstraction by trityl tetrafluoborate. This limits the usefulness of the above synthetic methods for polyfunctionalized cycloheptatrienes.