http://nopr.niscpr.res.in/handle/123456789/41209 2026-10-10T16:57:50Z http://nopr.niscpr.res.in/handle/123456789/41269 Title: A low-spin carboxyl-bonded iron(III) complex Authors: Karmakar, Soma; Chakravorty, Animesh Abstract: The ligand HON =C(Ph)N =N - C₆H₄CO₂H (H₂L) has afforded the low-spin (<i>S</i> = 1/2) iron(lll) complex, Et₄N[Fe(PhL)₂] which has been structurally characterised revealing the presence of <i>cis-</i>FeN₄O₂ coordination sphere. Carboxyl-bonded low-spin iron(lll) species are very rare. Spin-pairing contracts metal radius, the Fe - N and Fe - O lengths being significantly shorter than those in representative high-spin complexes. Page(s): 85-86 1996-02-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/41268 Title: Unusual conjugation pattern in a class of benzenoid hydrocarbons Authors: Gutman, Ivan; Ivanov-Petrović, Vesna; Pogodin, Sergey Abstract: Cyclic conjugation in angulenes (=unbranched catacondensed benzenoid hydrocarbons with one kink) has been examined. When moving along the hexagons of the angulene molecule cyclic conjugation varies in a rather non-uniform manner. This pattern of cyclic conjugation is at variance with predictions based on the analysis of Kekulé structures, and differs from what has been observed in the case of a number of other catacondensed benzenoid systems. Page(s): 87-92 1996-02-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/41267 Title: Dynamic instability in gas-liquid reactors-Oscillatory aerial oxidation of propionaldehyde Authors: Rastogi, R P; Misra, G P; Das, Ishwar; Jaiswal, Kiran Abstract: New experimental results on the oscillatory aerial oxidation of propionaldehyde in acetic acid/water medium in the presence of cobalt(ll) acetate and sodium bromide under controlled conditions are reported, Experiments have been performed in semi-batch reactor and continuously flow stirred tank reactor and the results have been compared with the corresponding results for benzaldehyde. The model of Guslander <i>et al </i> as well as an eleven variable model based on amplified mechanism of Roelofs <i>et aL </i> suitable for semi-batch reactor have been used for simulating the oscillatory features of aerial oxidation of aliphatic aldehydes. The rate constants have been assigned keeping in view the wide difference in the rate of formation of C₂H₅CO, and the reactivity of C₂H₅CO, C₂H₅CO₂ and C₂H₅CO₃ as compared to corresponding radicals related with benzaldehyde. Both the models predict oscillations in batch reactor in several variables including [Br^-]. However, latter model predicts qualitatively correctly the dependence of onset time/time period on [NaBr], [Co²⁺] and [C₂H₅CHO] whereas the former model only correctly predicts qualitatively the dependence of time period on [C₂H₅CHO]. Page(s): 93-101 1996-02-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/41266 Title: Synthesis, characterization and reactivity studies of some electrophilic mono- and binuclear nitrosyls of ruthenium(II) containing ketoximates Authors: Sinha, S; Basudhar, P R; Das, P K; Ghosh, B K Abstract: The reaction of [RuX₂(HL)(L)] (2) [X=CI or Br; HL (1)=PhC(O)C( = NOH)Ph (HL¹) or PhC(O)C(=NOH)Me (HL²)] with BuONO affords mononuclear [RuX(NO)L<img src='http://www.niscair.res.in/jinfo/equation36.gif' border=0>](<b>3</b>) or binuclear [RuX2(NO)Vh (<b>4</b>) nitrosyls depending on L;' <b>3</b> and <b>4</b> are also obtainable by reacting 2 with NaNO₂ in the presence of hydrochloric acid. Molecular weight determinations are 10 full consonance with mono- and binuclear formulations. Both 3 and 4 are electroactive and reductions characteristic of mono- and binuclear compositions are observable on the negative side of SCE. They react smoothly with acetylacetone (acacH) in presence of K₂CO₃ affording K[Ru(acamo)L<img src='http://www.niscair.res.in/jinfo/equation36.gif' border=0>] (<b>6</b>) and K[Ru(acac)(acamo) L²](<b>7</b>) [acamo is deprotonated CH₃C(= O)C( = NOH)[C(= O)CH₃] respectively. Page(s): 102-106 1996-02-01T00:00:00Z