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Poly -halogen complexes

A convenient method for the preparation of penta- and hexacoordinate silicon complexes was recently developed and reported [1]. The synthesis was based on an exchange reaction between poly-halogenated silanes with the O- or A-trimethylsilylated acylhydrazines and led to the formation of (0-Si)- and (N-Si)- mono and bis- chelate complexes (Scheme 1). [Pg.446]

Poly(styryldiphenylphosphine)-halogen. complexes are formed by addition of the halogen to a dichloromethane-swollen resin. The complexes react with epoxides to give trans-halohydrins in... [Pg.864]

The Ullman reaction has long been known as a method for the synthesis of aromatic ethers by the reaction of a phenol with an aromatic halide in the presence of a copper compound as a catalyst. It is a variation on the nucleophilic substitution reaction since a phenolic salt reacts with the halide. Nonactivated aromatic halides can be used in the synthesis of poly(arylene edier)s, dius providing a way of obtaining structures not available by the conventional nucleophilic route. The ease of halogen displacement was found to be the reverse of that observed for activated nucleophilic substitution reaction, that is, I > Br > Cl F. The polymerizations are conducted in benzophenone with a cuprous chloride-pyridine complex as a catalyst. Bromine compounds are the favored reactants.53,124 127 Poly(arylene ether)s have been prepared by Ullman coupling of bisphenols and... [Pg.346]

Complex (16), which has a similar structure to Co11 salen, catalyzes the electrocarboxylation of arylmethyl chlorides.274 The enhancement of the catalytic life of (16) as compared to Co-salen may be due to the absence of imino bond in its ligand. The catalytic reduction of halogenated compounds has also been attempted at poly[Mn(salen)]-coated electrodes (M = Ni,253 Co275), which might have potential use for determination of organohalide pollutants.275... [Pg.488]

The block copolymer of ethylene oxide and 3,3-dimethylthietane shows useful properties of complexing halogen and heavy metal salts (79MI51402). Thietanes can be polymerized with methylmagnesium iodide as well as with a variety of electrophiles such as methyl sulfate, trimethyloxonium tetrafluoroborate, triethylaluminum, boron trifluoride and phosphorus trifluoride (67IC1461, 67MI51400). Thietane (210) has been patented as a stabilizer for poly(vinyl chloride) (73USP3767615). [Pg.447]

The properties are very sensitive to composition and the charge carriers are apparently positive. Other studies have shown poly(acenaph-thalene) to be only slightly photo-conductive while the nitrated polymer exhibits a photocurrent dependent upon the degree of nitration (100). Since the number of mobile n electrons is the same as in poly (vinyl naphthalene), the authors conclude that some form of stereoregularity is required for enhanced conductivity. Complexes of poly(vinyl anthracene) with halogen molecules show enhanced conductivity and reduced activation energy which is thought to be typical of an electronic semiconductor (101). [Pg.341]

Complex compounds obtained by oxidative dissolution of elemental metals in the systems M°-ligand-solvent-HX (or halogen-substituted hydrocarbon), are represented by all types of complexes [509]. However, their ratio is not equal they are mainly molecular complexes and metal chelates the % -complexes and di(poly)-nuclear coordination compounds are not numerous. A large number of molecular (neutral and ionic) complexes, chelates, and their adducts, mostly with N-bases, are tabulated in monographs [201,202]. [Pg.274]

In some instances complexes were obtained derived from poly(l-pyrazolyl)borate ligands which never existed by themselves. This was the case with halogenation of the 4-position in HB[pz-3,5-(CH3)2]3Mo(CO)2NO to produce derivatives of the type HB[pz-3,5-(CH3)2-4-X]3Mo(NO)X2 and in HB[pz-3,5-(CH3y3Re(CO)3 which, on bromination, yielded the species HB[pz-3,5-(CH3)2-4-Br]3Re(CO)3 Another example is the formation of 20 by the reaction depicted in Eq. (7). [Pg.19]

Halogen oxidation of planar complexes, particularly of the nickel triads that contain bidentate glyoximes or macrocyclic ligands, such as, phthalocyanines, substituted porphyrins, or tetraazaannulenes, leads to highly conducting substances that may possess chains of metal atoms as well as chains of poly halides E... [Pg.210]


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Poly complexity

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