Reactions of dodecacarbonyltriruthenium with α,β-unsaturated ketones. Crystal and molecular structures of two reaction products

The thermal reactions of Ru₃(CO)₁₂ with RCOCH=CHPh (R=Me, p-MeC₆H₄) in hydrocarbon solvents lead to the formation of a series of complexes, several of which have been isolated as individual compounds by chromatography. The dinuclear complex Ru₂(-H)(CO)₆(-MeCOCH=CPh) and the tetranuclear complex Ru₄(-H)(-CO)(CO)₇(p-MeC ₆H₄ COCH=CPh)(-p-MeC₆H₄COCH=CPh)(₄-p-MeC₆H₃COCH=CHPh) are characterized by an X-ray structural study. The structures of other reaction products are discussed on the basis of spectral data. The reactions are accompanied by reduction of the starting enones to the corresponding unsaturated ketones.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1285–1293, July, 1993.     

Binuclear complexes from ω-cyanoalkyl derivatives of cyclopentadienylmanganese tricarbonyl and benzenechromium tricarbonyl

Conclusions The reaction of the-cyanoalkyl derivatives of cyclopentadienylmanganese tricarbonyl and benzenechromium tricarbonyl with chromium and tungsten carbonyls gave binuclear complexes with the same, as well as with different metals in the molecule.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 722–725, March, 1978.     

Preparation of unsymmetrical ruthenium bisarene cations

Conclusions A method was developed for the synthesis of ruthenium bisarene cations with various arenes [C₆H₆RuArene]²⁺ by heating [C₆H₆RuCl₂]₂ with the corresponding arene in heptane in the presence of AlCl₃.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1423–1425, June, 1985.     

Aspect-ratio dependent oscillatory thermocapillary convection in the floating half zone

The dependency of the critical Marangoni number on the geometrical aspect ratio of the floating half zone is essential to predict the onset of oscillatory thermocapillary convection.The experimental studies in the microgravity conditions on floating half zones of several centimeters in diameter have predicted that the critical Marangoni number increases with the increasing aspect ratio,and the terrestrial experimental studies have predicted the contradictory conclusion for floating half zones of several mil...     

Non-Gravitational Effects with Density-Matching in Evaluating the Influence of Sedimentation on Colloidal Coagulation

The method of density matching between the solid and liquid phases is often adopted to effectively eliminate the effect of sedimentation of suspensions in studies on dynamic behaviour of a colloidal system. However, the associated changes in the solvent composition may bring side effects to the properties investigated and therefore might lead to a faulty conclusion if the relevant correction is not made. To illustrate the importance of this side effect, we present an example of the sedimentation influence on the coagulation rate of suspensions of 2μm （diameter） polystyrene. The liquid mixtures, in the proper proportions of water （H2O）, deuterium oxide （D2O） and methanol （MeOH） as the liquid phase, density-matched and unmatched experiments are performed. Besides the influence of viscosity, the presence of methanol in solvent media, used to enhance the sedimentation effect, causes significant changes （reduction） in rapid coagulation rates compared to that in pure water. Without the relevant corrections for those non-gravitational factors it seems that gravitational sedimentation would retard the coagulation. The magnitude of the contribution from the non-gravitational factor is quantitatively determined, making the relevant correction possible. After necessary the influence of the sedimentation on coagulation rates at corrections for all factors, our experiments show that the initial stage of the coagulation is not observable.     

Chromium-tricarbonyl complexes of phenyl-containing cyclosiloxane

Conclusions The reaction of different cyclosiloxanes with chromium-carbonyls was studied. Mono- and binuclear chromium-tricarbonyl complexes of phenyl-containing cyclosiloxanes were obtained for the first time.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2060–2063, September, 1987.     

Improved method for the preparation of a ruthenium carbonylcarbide cluster,Ru6C(CO)17

An improved method has been developed for the synthesis of the ruthenium carbonylcarbide cluster Ru₆C(CO)₁₇ by heating Ru₃(CO)₁₂ in octane at reflux.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1893–1894, August, 1990.