Some observations on the interdependence of cyanide concentration and atomization efficiency in the nitrous oxide-acetylene flame

A relationship is derived between CN concentration and atomization efficiency in the C₂H₂-N₂O flame. The relationship is examined under various experimental conditions and β values are estimated for a number of elements. The possibility of complex vapour phase oxide formation by U is considered.     

Excess enthalpies and excess volumes of 1-nitropropane +, and 2-nitro-propane +, each of several non-polar liquids

Excess molar enthalpies H_m^E and excess molar volumes V_m^E have been measured for xC₃H₇NO₂ + (1 ? x)c-C₆H₁₂ at 298.15 and 318.15 K; +(1 ? x)CCl₄ at 298.15 and 318.15 K; +(1 ? x)C₆H₆ at 298.15 and 318.15 K; +(1 ? x)C₆H₁₄ (V_m^E only) at 298.15 K; +(1 ? x)p-C₆H₄(CH₃)₂ at 298.15 K; and for xCH₃CH(NO₂)CH₃ + (1 ? x)c-C₆H₁₂ at 298.15 and 318.15 K; +(1 ? x)CCl₄ at 298.15 and 318.15 K; +(1 ? x)C₆H₆ at 298.15 K; +(1 ? x)C₆H₁₄ at 298.15 K; +(1 ? x)(CH₃)₂CHCH(CH₃)₂ for H_m^E at 318.15 K and for V_m^E at 298.15 K; and +(1 ? x)C₁₆H₃₄ at 298.15 K. The H_m^E′s were determined with an isothermal dilution calorimeter and the V_m^E′s with a continuous-dilution dilatometer. Particular attention was paid to the region dilute in nitroalkane. In general H_m^E is large and positive for (a nitropropane + an alkane), less positive for (a nitropropane + tetrachloromethane), and small for (a nitropropane + benzene) and for (a nitropropane + 1,4-dimethylbenzene). The mixture with hexadecane shows phase separation. V_m^E is large and positive for (1-nitropropane + cyclohexane), less positive for (1-nitropropane + hexane), and S-shaped for (1-nitropropane + tetrachloromethane) with negative values in the 1-nitropropane-rich region. For (1-nitropropane + benzene) and for (1-nitropropane + 1,4-dimethylbenzene) V_m^E is negative. For mixtures with 2-nitropropane the results are similar except that for benzene V_m^E is S-shaped with positive values in the 2-nitropropane-rich region.     

(π-Cyclopentenyl)(π-cyclopentadienyl)nickel: A novel catalyst for the conversion of ethylene to 1-butene and n-hexenes

(π-Cyclopentenyl)(π-cyclopentadienyl)nickel, (h⁵-C₅H₅)Ni(h³-C₅H₇), is a novel, highly active, unicomponent catalyst for the conversion of ethylene to n-butenes and n-hexenes at 145–150° C. At high conversions of ethylene (70–90%), the dimeric product (80–86% yield) contains a high percentage (90–82%) of 1-butene. Experimental evidence is presented which strongly indicates that the cyclopentadienyl group remains bonded to the nickel during catalysis while the cyclopentenyl group is labile. A possible mode of activation is the reversible elimination of cyclopentadiene from (h⁵-C₅H₅)N₁(h³-C₅H₇) to generate π-cyclo pentadienylnickel hydride as a catalytically active intermediate. An improved synthesis of the title compound (70% yield) by direct hydrogenation of nickelocene is also reported.     

Organostibines as ligands. Synthesis of dimethyl(α-picolyl)stibine,dimethyl(8-quinolyl)stibine,and (R;S)-methylphenyl(8-quinolyl)stibine and some transition metal derivatives

The unsymmetrical mono-tertiary stibines dimethyl(α-picolyl)stibine (picstib), dimethyl(8-quinolyl)stibine (quinstib), and (R;S)-methylphenyl(8-quinolyl)stibine (R;S-quinstib) have been synthesised and the square-planar complexes [MX₂(picstib)], [MX₂(quinstib)] (where M = Pd or Pt and X = Cl, Br, I or SCN) and [MCl₂(R;S-quinstib)] (where M = Pd or Pt) isolated. The thiocyanato derivatives display linkage isomerism. The octahedral complexes [M(CO)_4-(picstib)] and [M(CO)₄(quinstib)] have also been prepared from the metal hexacarbonyls and the appropriate ligands by UV irradiation in tetrahydrofuran.