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Ethyl (Z)-2-(2,3-dihydro-1,3-dioxo-1H-isoindol-2-yl)-3-(dimethylamino)propenoate was prepared in one step from ethyl (2,3-dihydro-1,3-dioxo-1H-isoindol-2-yl)acetate and bis(dimethylamino)-tert-butoxymethane and treated with various amines and hydrazines to afford the corresponding amino substituted products. Reactions of the titled compound with N,N'-, C,N-, and C,O'-ambident nucleophiles in refluxing acetic acid furnished the corresponding fused pyrimidinones, quinolizinones, and pyranones.

Crystals of (NH3OH)2TiF6ċ2H2O have been isolated. The compound crystallizes in the monoclinic system (P21/c, No. 15) with cell parameters of a=6.203(1) A, b=10.057(1) A, c=7.464(1) A, and β=110.653(6)°. Reactions in the system In (OH)3– NH3OHF – HF have been investigated. Crystals of (NH3OH)3InF6 were isolated from aqueous solution. The compound crystallizes in the trigonal system (R3c) with a=b=c=7.764(2) A, α=β=γ=97.21(4)°. The thermal decomposition of both compounds was studied by TG and DSC analysis; the decomposition products were characterized by X-ray powder diffraction.

Crystals of (NH3OH)3GaF6 have been isolated from aqueous solution. The compound crystallizes triclinic, with cell parametersa=6.539(5) A,b=6.924(5) A,c=9.403(1) A, α=87.01(9)°, β=83.98(8)°, γ=70.28(8)°. The thermal decomposition was studied by TG and DSC analysis.

Hydroxylammonium fluorozirconates have been investigated. Two new microcristalline phases have been isolated from aqueous solutions: (NH3OH)2ZrF6 (1) and (NH3OH)3ZrF7 (2). The crystals were prepared by slow evaporation of the solution of NH2OH, Zr, and HF. Different compositions of the crystals were achieved by varying the molar ratios of the components. They were characterized by thermal analysis, vibrational spectroscopy, and structure (single crystal x-ray methods). (NH3OH)2ZrF6 (1) crystallizes triclinic, P\(\overline 1 \) (No.: 2),a=7.400(2),b=7.609(2),c=7.887(2) A, α=57.29(3)°, β=62.16(3)°, γ=67.83(2)°. (NH3OH)3ZrF7 (2) crystallizes triclinic, P\(\overline 1 \) (No.: 2),a=7.128(1),b=7.989(1),c=8.888(1) A, α=109.72(1)°, β=91.01(1)°, γ=104.27(1)°.

Hydroxylammonium fluoride was prepared in aqueous solution by the reaction of hydroxylamine with aqueous hydrogen fluoride. The solubility in water (148.7 g/100 g) and ethanol (0.146 g/100 g), the density (1.621±0.005 g/cm3) and the metling point (97.8±2 °C) of the compound have been determined. [NH3OH]F crystallizes orthorombic, Pabc,a=6.490(1) A,b=9.799(1) A,c=13.519(2) A.

Oxidative dimerizations of some naphthalene derivatives were studied. With vanadium oxytrichloride either a new C-C bond formation occured or the reagent caused chlorination of the ring. Attempts to induce photochemically a new C-C bond failed.

Complexes of the type Cs[Ln(SO4)2(H2O)3]H2O, (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) were prepared from aqueous solution. The compounds are all isomorphous and crystallise monoclinic, space group P21/c,Z=4. Unit cell parameters were determined by the single crystal technique and correlated to the ionic radii of Ln3+.

Crystals of the title compound were prepared by heating Cs[Pr(SO4)2(H2O)3]·H2O with H2SO4 at 300°C. CsPr(SO4)2 crystallizes in the orthorhombic space group Pnna witha=9.497(3),b=14.106(5),c=5.457(1) A,p0=4.20,pc=4.236 gcm-3,Z=4. The structure, solved by the heavy-atom method from X-ray diffractometer data, was refined by least-squares techniques to R=0.023. The praseodymium atom is eight coordinated by eight oxygen atoms in the form of a distortedArchimedian antiprism. The antiprisms together with sulphur atoms form a layer-like structure parallel to thexz plane. The caesium atoms, which lie between the layers, have a coordination number of fourteen.

The title compound (C6H8N)2Mo2I6(H2O)2 crystallizes in theP¯1 space group, witha = 8.127(3),b = 8.337(3),c = 10.415(4) A, α = 73.99(2), β = 84.35(2), γ = 73.91(2) ° andZ = 1. The structure was solved by direct methods and refined to the unweighted and weighted residuals of 0.044 and 0.052. The structure is characterized by the eclipsed configuration of the iodide ions and water molecules within Mo2I6(H2O) 2 2− ion and very short Mo-Mo bond distance 2.115(1) A. Three independent Mo-I distances are 2.784(1), 2.760(2) and 2.797(1) A. 4-Methylpyridinium ion is planar within 0.02° A. The compound is isostructural with (C6H8N)2Mo2Br6(H2O)2.

Mo2Cl4Pic4·CHCl3 (A) (Pic=4-methylpyridine) and Mo2Br4Pic4 (B) crystallize in the monoclinic space group.A inC2/c (No. 15) witha=15.175 (4),b=10.847 (2),c=19.946 (6) A and β=104.52 (2)°;Do=1.71 (2),Dc=1.72 gcm−3 forZ=4.B inP2l/n (No. 14) witha=9.270 (3),b=16.614 (5),c=9.305 (3) A and β=91.96 (5)°;Do=2.03 (3),Dc=2.05 gcm−3 forZ=2.

Es werden die Resultate des isothermen Zerfalles und der Reduktion vonstandardisiertem Ammoniumpolyuranat im Bereich von 285 bis 463° C (in Wasserstoff) wiedergegeben. Der Zerfall zu UO3 wurde schon bei einer Temp. unter 290° C festgestellt, diese Phase blieb jedoch darauf stabil bis 320° C. Zwischen 320° C und 380° C verlauft die Reduktion zu U3O8, uber 380° C aber zu UO2. Die Aktivierungsenergien bei der Reduktion von UO3 zu U3O8 und von U3O8 zu UO2 wurden berechnet, und zwar 32,2 kcal/g-mol und 41,7 kcal/g-mol. Die Ergebnisse konnen mit den Literaturangaben fur die Reduktion der einzelnen Phasen UO3 und U3O8 verglichen werden. Die beobachteten Unterschiede weisen auf den Einflus der Aktivitat der Praparate hin.

Mit einem modifiziertenHoppler-Konsistometer verfolgten wir die Temperaturabhangigkeit der Stempelsenkung bei verschiedenen Zusammensetzungen in den Systemen NaNO3−KNO3 und ZnSO4−KCl. Die Ergebnisse zeigen, das man auf Grund solcher Messungen Aussagen uber die Form der Zustandsdiagramme machen kann. Auserdem erganzen die Messungen im System ZnSO4−KCl die Literaturangaben.

Die Resultate isothermer Messungen der Sorption der Stickoxyde an CaO bei verschiedenen Drucken (0,05 bis 1 Atm) und bei Temperaturen von 20 bis 650°C werden wiedergegeben. Im untersuchten Temperaturintervall verlauft die Reaktion unter Bildung von Calciumnitrat mit kleinen Nitritbeimengungen. In bezug auf die Kinetik der Bildung kann man das untersuchte Temperaturintervall fur 1 Atm Stickoxyde-Druck in drei Bereiche einteilen: unter 50°C, von 50 bis 400°C und von 450 bis 610°C. In den ersten zwei Bereichen findet die Reaktion im System fest—gasformig statt, wahrend im dritten die Gasphase mit einer mehr oder weniger ausgepragten Schmelze reagiert.

Hydrazinium-Monofluorid N2H5F, das einzige noch unbekannte Hydrazinium-Monohalogenid, wurde im Nuklearinstitut “Jožef Stefan” synthetisiert. Farblose durchsichtige nadelformige Kristalle (Dichte 1,47 g/cm3) wurden uns fur eine Strukturanalyse zur Verfugung gestellt.