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Supported catalysts for ethylene polymerization have been prepared by interaction of Cp2ZrX2 (Cp=η5-C5H5, X=Cl or CH3) with silica chemically modified by (CH3)3SiCl (TMCS) or trialkylaluminium compounds AlR3 (R=C2H5 (TEA) and i C 4H9 (TIBA)). The interactions between the modificators and the silica surface have been examined by 1 H solid-state MAS NMR spectroscopy, DRIFTS and chemical analysis. The Cp2Zr(CH3)2/SiO2–TMCS catalyst showed a fairly high activity in ethylene polymerization (30–300 kg PE(mol Zr·h·bar)−1) even in the absence of any cocatalysts specially added. The addition of the cocatalyst (MAO or TIBA) led to a further increase in the activity of the supported catalysts. Polyethylene obtained with the Cp2Zr(CH3)2/SiO2–TMCS catalyst without any cocatalyst consisted of uniform polymer particles of a spherical shape replicating that of the silica particles, whereas the shapeless aggregates of finely dispersed polymer particles similar to those usually obtained with homogeneous systems were produced with the same supported catalyst in the presence of the MAO cocatalyst.

Treatment of the azines CF3CXNNCXCF3 [X=Cl (1a) and X=I (1b)] with diamines H2N(CH2)nNH2 (n=2, 3, 4, 6, 9, 12) gives 2:1 substitution products, the open-chain dihalogenotetraenes CF3CXNNC(CF3)NH(CH2)nNHC(CF3)NNCXCF3, and/or 2:2 substitution products, the cyclotetraenes CF3 CNNC(CF 3 )NH(CH 2 ) n NHC(CF 3 )NNC(CF 3 )NH(CH 2 ) n N H; the former compounds are the precursors of the cyclic compounds. In the reaction of azine 1a with 1,6-diaminohexane, a further product, the bis(triazole) CF3CNNC(CF3)N(CH2)6NC(CF3)NNCCF3, is also formed. The reaction of azine 1a with 1,2-diaminobenzene gives 2-(trifluoromethyl)benzimidazole in excellent yield

2,5-Dichloro-1,1,1,6,6,6-hexafluoro-3,4-diazahexa-2,4-diene ( 1 ) has been prepared in goodyield (60%) by the reaction of 1,2-bis(trifluoroacetyl)hydrazine with a mixture of N,N -dimethylaniline hydrochloride and phosphoryl chloride. Nucleophilic displacement ofchlorine from azine 1 occurs readily on reaction with primary amines RNH 2 (RPr i , Bu s ,Ph, 4-FC 6 H 4 , 2,6-Cl 2 C 5 H 2 NCH 2 -4) and with secondary amines (morpholine and Et 2 NH);in general, mono- or di-substitution can be achieved by varying the azine/amine ratio(1:2 or 1:4). The products are the azines CF 3 (NRR′)NNCClCF 3 ( 7 ) (RH, R′Pr i ;RR′Et) and CF 3 C(NRR′)NNC(NRR′)CF 3 ( 8 ) (RH, R′=Pr i , Bu s and 2,6-Cl 2 pyCH 2 -4; RR′: Et; RR′CH 2 CH 2 OCH 2 CH 2 ) and the imidoyl tautomersPhNC(CF 3 )NHNCClCF 3 ( 9a ) and ArNC(CF 3 )NHNHC(CF 3 )NAr ( 110 ) (ArPh and4-FC 6 H 4 ). On heating at temperatures up to 120 °C, the compounds 10a (ArPh), 10b (Ar4-FC 6 H 4 ) and 9a undergo cyclisation (with elimination of ArNH 2 or HCl) to affordthe corresponding 4-aryl-4 H -1,2,4-triazoles ( 22 ); the azine 8a (R=Pr i ) does not cycliseunder these conditions. The azine 7a (RH, R′Pr i ) on hydrolysis (NaOH/EtOH thenH 3 O + ) gives the trifluoroacetylhydrazine Pr i NC(CF 3 )NHNHCOCF 3 ( 20 ) in excellent yield(92%).

Exposure of a mixture of the title azine (1) and triethylamine (1:2 molar ratio) to daylight gives as major products, triethylamine hydrochloride and the Δ2-azetine CF3 CCHCH(NEt 2 )N NCClCF3 (3), together with trifluoroacetonitrile and tar; a single electron transfer (SET) mechanism is proposed involving the intermediacy of the enamine Et2NCHCH2. In contrast the reaction of azine (1) with tri-n- propylamine in light affords the amine hydrochloride, the substituted azine CF3CClNNC(NPrn2)CF3 (14) and tar. Treatment of the heterocycle (3) with diethylamine results in replacement of Cl by NEt2 to give the azetine (6) which is also formed when the azine CF3CClNNC(NEt2)CF3 (7) is heated with triethylamine.

Treatment of tetrachlorophthalic anhydride (I) with zinc dust and aqueous sodium hydroxide produces 3,4,6-trichlorophthalic acid (II) which under similar reaction conditions yields predominantly a mixture of 3,6-dichlorophthalic acid (III) and 3-chlorophthalic anhydride (IV).

Treatment of tetrachlorophthalic anhydride (I) with zinc dust and aqueous sodium hydroxide produces 3,4,6-trichlorophthalic acid (II) which under similar reaction conditions yields predominantly a mixture of 3,6-dichlorophthalic acid (III) and 3-chlorophthalic anhydride (IV).

A room temperature method for the conversion of perfluoroalkyl iodides to α-perfluoroalkyl carbinols under Pd or Ni catalysis is reported. The use of trifluoromethyl bromide provides an economical procedure for trifluoromethyl substituted carbinols.

Le pentafluoroethyllithium(I) s'additionne aux aldehydes et cetones avec un rendement de 80 a 100% pour donner les alcools secondaires et tertiaires correspondants. Il s'additionne aux esters pour donner soit des cetones soit des alcools tertiaires selon la structure de l'ester et les conditions reactionnelles

Pentafluoroethyl iodide undergoes a rapid exchange reaction with methyllithium at −78°C in the presence of ketones to produce pentafluoroethyl-substituted tertiary carbinols in high yield.

A room temperature method for the conversion of perfluoroalkyl iodides to α-perfluoroalkyl carbinols under Pd or Ni catalysis is reported. The use of trifluoromethyl bromide provides an economical procedure for trifluoromethyl substituted carbinols.

Le pentafluoroethyllithium(I) s'additionne aux aldehydes et cetones avec un rendement de 80 a 100% pour donner les alcools secondaires et tertiaires correspondants. Il s'additionne aux esters pour donner soit des cetones soit des alcools tertiaires selon la structure de l'ester et les conditions reactionnelles