Phenylenes complexation

Triply bridging orf/io-phenylene complexes sometimes arise in curious ways. In the reaction of Os3(CO)10(MeCN)2 with salicylaldehyde benzy-limine one would naively expect that coordination would be through N and O atoms as with other metal systems. The first formed compound (40, Scheme 6) results from ortho metallation while, of the three isomeric decarbonylation products (41 to 43), compound 43 contains only Os—C bonds to the ligand and is a ring-substituted version of Os3H2(C6H4)(CO)9 (Scheme 6) (237). 

The five-membered nickel ring 160a can be obtained in both ways [Eq. (121)] 124, 755) the diarsano-o-phenylene complex 160b has been synthesized via ring expansion 41) (see Table VII). 

Jahns et al. (1992) investigated the possibility of an agostic interaction in two para-dimetallated 0-phenylene complexes [((cp )2R)2C6H4] for R=Sc and Lu using the INDO/1 method. The crystal structure of these binuclear complexes is known. They... 

Yaniger et al reported the first example of poly(-arylene) metal complexes in 1984 [130], They prepared poly(p-phenylene) complexes of M(CO)3 (58, M = Cr, Mo) by reaction of insoluble powdery poly(/7-pheny-lene) with M(CO)3(CH3CN)3 in boiling hexane. The polymer complexes thus obtained are insoluble and characterized by FT-IR spectroscopy and elemental... 

Guest Chemistry of Rotaxanes and Catenanes Application of a Polarizable All-Atom Force Field to Cyclobis(paraquat-p-phenylene) Complexes with Disubstituted Benzenes and Biphenyls. 

Halophenols without 2,6-disubstitution do not polymerize under oxidative displacement conditions. Oxidative side reactions at the ortho position may consume the initiator or intermpt the propagation step of the chain process. To prepare poly(phenylene oxide)s from unsubstituted 4-halophenols, it is necessary to employ the more drastic conditions of the Ullmaim ether synthesis. A cuprous chloride—pyridine complex in 1,4-dimethoxybenzene at 200°C converts the sodium salt of 4-bromophenol to poly(phenylene oxide) (1) ... 

The oxidative coupling of 2,6-dimethylphenol to yield poly(phenylene oxide) represents 90—95% of the consumption of 2,6-dimethylphenol (68). The oxidation with air is catalyzed by a copper—amine complex. The poly(phenylene oxide) derived from 2,6-dimethylphenol is blended with other polymers, primarily high impact polystyrene, and the resulting alloy is widely used in housings for business machines, electronic equipment and in the manufacture of automobiles (see Polyethers, aromatic). A minor use of 2,6-dimethylphenol involves its oxidative coupling to... 

Respiratory sensitizers Isocyanates proteolytic enzymes p-phenylene diamine complex salts of platinum cyanuric chloride. ... 

The crystal of 2 OPr recrystallized from EtOH/H20 solution, and the mixed crystal of the same ethyl and propyl cinnamate derivatives (2 OEt and 2 OPr), on photoirradiation for 2h at room temperature with a 500 W super-high-pressure Hg lamp, afforded the highly strained tricyclic [2.2] paracyclophane (2 OEt-2 OPr-cyclo) crystal quantitatively (Maekawa et ai, 1991b). A crystal structure analysis was carried out of a single crystal of the complex of 2 OEt-2 OPr-cyclo with HFIP (recrystallization solvent) in a 1 2 molar ratio. Fig. 13 shows the molecular structure of 2 OEt-2 OPr-cyclo viewed along the phenylene planes. The short non-bonded distances and deformation of the benzene rings, as seen in Fig. 13, are common to those of [2.2] paracyclophanes, as previously reported (Hope et ai, 1972a,b). 

Verdet and Stille1 employed brominated poly(phenylene oxide) intermediates in an effort to synthesize more stable catalyst supports containing (cyclopentadienyl)metal complexes. Treatment of poly(oxy-2,6-dimethyl-l,4-phenylene) with N-bromosuccinimide under photolytic conditions produced only the bromomethyl derivative if the D.F. did not exceed 0.35. Subsequent treatment of the bromomethylated polymer with sodium cyclopentadienide afforded the cyclopentadienyl functionalized polymer, 5, but the reaction was accompanied by crosslinking and it was not possible to remove the bromomethyl substituents quantitatively. 

Reduction of Poly(2-cyano-l,3-phenylene arylene ether), 20 Twenty-five mL of a 1.0 M solution of lithium aluminum hydride (LAH) in THF was cooled to 0° C before adding a solution of 1.64 g (5.0 meg) of 20 in 120 mL of THF. The resultant slurry was stirred for 24 h at 0° C, refluxed for 1 h, recooled to 5° C, and the excess LAH decomposed with 2 mL of water. The volume of the solution was reduced to 25 mL before pouring the mixture into 500 mL of 5% HC1 to dissociate the amine aluminum salt complex and precipitate the polymer. The polymer was recovered by filtration, reslurried in 20 mL of water and the pH adjusted to 9.0 with NaOH. After recovery of the neutralized polymer was recovered, it was dried in vacuo redissolved in CHC13, and reprecipitated using water as the nonsolvent. Final drying in vacuo for 24 h at 35° C left 1.2 g (72.3%) of poly[oxy-l,4-phenylene-(l-methylethylidene)-l, 4 -phenylene-oxy-(2"-aminomethyl)-l",3"-phenylene], 21, [n] (CHCI3) 0.3 dl/g. 

The ligands phenylene-l,2-dithiolate, or its 4-methyl derivative, have been thoroughly studied in their gold(I) complexes and di-, tri-, and tetranuclear derivatives have been prepared of the type... 

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