Synthesis and investigation of organosilicon dendrimers based on octavinylsilsesquioxane and sulfenyl chlorides of metal acetylacetonates

The addition of sulfenyl chlorides of metal acetylacetonates to octavinylsilsesquioxane was studied. The addition was shown to proceed at four of the eight vinyl groups of the octavinylsilsesquioxane, without the formation of cross-linked polymers. This allowed us to synthesize with high yields new non-functianalized and functianalized dendrimers based on octavinylsilsesquioxane and the sulfenyl chlorides of metal acetylacetonates.     

Addition of sulfenyl chlorides to α-fluoroacrylates

Conclusions -Fluoroacrylates add sulfenyl chlorides in such a manner that the methylthio group adds exclusively, and the phenylthio group adds predominantly, to the-carbon atom.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1412–1414, June, 1973.     

Fractional sublimation of various metal acetylacetonates

A simple fractional sublimator is described which possesses a continuous temperature gradient along its length. Samples are placed in the high temperature end of the tube and volatilized at 1-mm pressure. The gases are moved through the tube with air as a carrier. The metal chelates recrystallize on the walls of the tube in discrete and reproducible temperature zones. Characteristic recrystallization zones are reported for 21 metal acetylacetonates. The chelates can be grouped according to zone temperatures into 6 fairly distinct groups over the range 15 to 200°, which makes many separations possible. Separations of mixtures of Mg, Al and Be ; Ni, Fe and Be ; and, Cu and Fe were studied quantitatively. The separations achieved compared favorably with those reported by gas chromatography. The method offers real promise for the purification of a number of metals but appears especially good as a method for beryllium and certain platinum group metals.     

The solubility parameters of metal acetylacetonates

Solubility parameters for Be(acac)₂ and Th(acac)₄ calculated from viscosity measurements on dilute solutions in benzene at 25.0°C have been compared with data for tris-acetylacetonates of Al, Cr, Mn, Fe and Co. In non-polar solvents the value does not vary much with the nature of the metal (average δ₂ = 9.4 ± 0.4) nor do the molar volumes, which can be calculated from V_m = 90.5n ± 5%.     

Diamagnetic muon yields of metal acetylacetonates

Diamagnetic muon yields /P_D/ in various metal acetylacetonates were measured at room temperature by the muon spin rotation technique. We have found a clear difference in P_D between complexes of typical elements and those of transition elements. We suggest that partially filled inner orbitals play some important role in determining the diamagnetic yield in these complexes.     

Reaction of 1,2-dithiolan- and 1,2-dithiolen-3-ones with sulfenyl chlorides

Conclusions The 1,2-dithiolan- and l,2-dithiolen-3-ones are cleaved by CH₃SC1 and C₆H₅SC1 at the S-CO bond to respectively give the saturated and unsaturated acid chlorides of -alkyl-(aryl)trithiocarboxylic acids.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2610–2613, Novmeber, 1975.     

3-R-Thio- and 3-R-Oxy-substituted metal acetylacetonates

New S- and O-substituted metal acetylacetonates were prepared from phenylthio-, butylthio-, benzenesulfonato-, and 3-acetoxyacetylacetone and appropriate metal salts. The spectral characteristics of the compounds were obtained. The effect of the α-substituent on the stability of the chelates under the conditions of chromatographic separation on silica gel was revealed. The reactivity of the acetate group bonded to the chelate ring is decreased, which does not allow preparation of new substituted complexes by common transformations of esters.