87604-18-0Relevant articles and documents
Catalyst system for producing polyethylene copolymers in a high temperature solution polymerization process
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, (2019/06/10)
Catalyst system for producing ethylene copolymers in a high temperature solution process, the catalyst system comprising (i) a metallocene complex of formula (I) wherein M is Hf X is a sigma ligand, L is a bridge of the formula —SiR82—, wherein each R8 is independently a C1-C20-hydrocarbyl, tri(C1-C20-alkyl)silyl, C6-C20-aryl, C7-C20-arylalkyl or C7-C20-alkylaryl n is 0, 1 or 2 R1 and R1′ are the same or can be different and can be a linear or branched C1-C6-alkyl group, R2 and R2′ are the same or are different and are a CH2—R9 group, with R9 being H or linear or branched C1-C6-alkyl group R5 and R5′ are the same or are different and can be H or a linear or branched C1-C6-alkyl group or a OR group, wherein R is a C1-C6-alkyl group R6 and R6′ are the same or are different and can be H or a C(R10)3 group, with R10 being the same or different and R10 can be H or a linear or branched C1-C6-alkyl group or R5 and R6 and/or R5′ and R6′ taken together form an unsubstituted 4-7 membered ring condensed to the benzene ring of the indenyl moiety, and R7 and R7′ can be the same or are different and can be H or a linear or branched C1-C6-alkyl group (ii) an aluminoxane cocatalyst and/or (iii) a boron containing cocatalyst and (iv) optionally an aluminum alkyl compound.
Preparation method of 2-[(5-bromo-2-methylphenyl)methyl]-5-(4-fluorophenyl)thiophene
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Paragraph 0005; 0012; 0014, (2017/08/31)
The invention provides a preparation method of 2-[(5-bromo-2-methylphenyl)methyl]-5-(4-fluorophenyl)thiophene. The preparation method comprises the following steps: reacting 4-bromotoluene used as an initial raw material with paraformaldehyde and concentrated hydrochloric acid under the catalysis of zinc chloride to prepare 2-methyl-5-bromobenzyl chloride, dissolving the 2-methyl-5-bromobenzyl chloride and 2-p-fluorophenylthiophene in ethyl acetate, and carrying out a reaction at 80 DEG C under the catalysis of zinc chloride to synthesize the 2-[(5-bromo-2-methylphenyl)methyl]-5-(4-fluorophenyl)thiophene. The preparation method has the advantages of low price and easy obtaining of raw materials, diversified selection of the raw materials, easiness in realization, easiness in control, high purity of the final product, no dangerous processes, simple device, novel synthesis route, short synthesis route, increase of the productivity, and reduction of the production processing cost.
CATALYSTS
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, (2016/01/09)
A catalyst comprising (i) an asymmetric complex of formula (I) wherein M is zirconium or hafnium; each X is a sigma ligand; L is a divalent bridge selected from —R′2C—, —R′2C—CR′2—, —R′2Si—, —R′2Si—SiR′2—, —R′2Ge—, wherein each R′ is independently a hydrogen atom, C1-C20-alkyl, tri(C1-C20-alkyl)silyl, C6-C20-aryl, C7-C20-arylalkyl or C7-C20-alkylaryl; R2 and R2′ are each independently linear C1-10 hydrocarbyl; R5 and R5′ are each independently hydrogen or a C1-20 hydrocarbyl group; R6 and R6′ are each independently hydrogen or a C1-20 hydrocarbyl group; R7 is hydrogen or a C1-20 hydrocarbyl group or is ZR3; Z is O or S, preferably O; R3 is a C1-10 hydrocarbyl group; Ar is an aryl or heteroaryl group having up to 20 carbon atoms optionally substituted by one or more groups R8; Ar′ is an aryl or heteroaryl group having up to 20 carbon atoms optionally substituted by one or more groups R8′; and R8 and R8′ are each independently is a C1-20 hydrocarbyl group; with the proviso that at least one of R6 or R7 is not H; and (ii) a cocatalyst comprising a compound of a group 13 metal, e.g. boron.
