Transition-metal-free controlled polymerization for poly(p-aryleneethynylene)s
نویسندگان
چکیده
منابع مشابه
Photoinitl&tion of Free-radical Polymerization by Transition Metal Derivatives
Two types of photoinitiator are considered: (1) transition metal complexes (mainly carbonyls), (2) chelates of transition metals. In systems of type (1) the metal is in a low oxidation state and an organic halide is generally, but not always, present; on thc other hand, in (2) the metal is initially in a high oxidation state. Comparison between photoand thermal-initiation is made for each type....
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a series of dissymmetric dinuclear complexes were synthesized, as dual site catalysts in ethylene polymerization,by coupling the allylated a-diimine complexes of the metals ti, zr, v, ni and pd with the ansa-zirconocenecomplex [c5h4-sih(me)-c5h4]zrcl2 possessing a hydride silane moiety. the different stages of syntheses includedthe formation of bis(cyclopentadienide)methyl silane which was util...
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Tertiary silane 1H , 2-[(diphenylsilyl)methyl]-6-methylpyridine, reacts with tris(pentafluorophenyl)borane (BCF) to form the intramolecular pyridine-stabilized silylium 1+ -HBCF. The corresponding 2-[(diphenylsilyl)methyl]pyridine, lacking the methyl-group on the pyridine ring, forms classic N(py)→B adduct 2H -BCF featuring an intact silane Si-H fragment. Complex 1+ -HBCF promotes cleavage of t...
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ژورنال
عنوان ژورنال: Chemical Science
سال: 2015
ISSN: 2041-6520,2041-6539
DOI: 10.1039/c4sc02872d