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A new method for preparation of zirconium and hafnium phenoxyimine complexes L 2 MCl 2 (L is N (3,5 di tert butylsalicylidene) 2,3,5,6 tetrafluoroanilinate anion, M = Zr, Hf) by the solid state interaction of N (3,5 di tert butylsalicylidene) 2,3,5,6 tetrafluoroaniline, the cor responding metal chlorides, and sodium hydride under mechanical activation followed by heating of the activated mixture was developed. The obtained complexes have a high catalytic activity in the reaction of ethylene polymerization.

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A mechanoactivated solid-state oxidative decyclization of l-alkylcycloalkanols under the action of the Pb(OAc)4--MX or Mn(OAc)3--MX systems (MX is a metal halide) was carried out for the first time. The reaction affords exclusively ta-haloalkanones.Key words: mechanical activation, oxidative decyclization, tertiary cyclic alcohols, lead tetraacetate, manganese triacetate, 0~-haloalkanones.Oxidative decyclization of 1-alkylcycloalkanols (1) with lead tetraacetate is one of the most convenient methods for the synthesis of substituted ketones. Oxoalkyl radicals RCOCH2(CH2),C'H 2 (R = Ct--C 9 alkyl; n = 2--5) generated in the reaction of cyeloalkanols I with lead tetraacetate I are oxidized with a Pb(OAc)4--Cu(OAc)2 system into unsaturated ketones in quantitative yields, z selectively transformed into co-halo-or 0~-pseudohaloalkanones under the action of a Pb(OAc)4--metat halide(pseudohalide) system, 3,4 and recombined with each other in the presence of a Pb(OAc)4~AgOAc systerri to givedicarbonyl compounds. 5 All the above processes needed a solvent (benzene) and pyridine, which accelerates the oxidation, and were carried out at 80 ~ Unlike lead tetraacetate, manganese triacetate efficiently oxidizes only l-methylcyclobutanol (la), while cycloalkanols I with a larger ring size are inert with respect to this oxidant. 6In the present work, in continuation of the study of mechanoactivated oxidation of organic compounds with Pb TM and Mn m compounds in the absence of a solvent 7 we carried out for the first time the oxidation of cycloalkanols 1 (ring size C4--C 6) with the Pb(OAc) 4-MX or Mn(OAc)3--MX systems (M = Li, Na, or K; X = CI or Br). Reaction mixtures were mechanically activated using vibration ball mills in sealed steel reactors. The reaction began at 20 ~ but the mechanical energy supplied to the reactants increased the temperature by I0 to 15 ~ over 4 h. Cycloalkanols I react with the oxidizing systems to give a~-chloro(bromo)alkanones (2).At the first stage, when the reaction mixture (a solid mass of lead tetraacetate and halide MX, saturated with cyctoalkanol 1) is mechanically activated, complex compounds M2[Pb(OAc)4X2] seem to be formed. The formation of such complexes from Pb(OAc) 4, K2[Pb(OAc)6], and K2[Pb(OAc)4CI2] was reported previously. 8.9

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