Perfluoro phenyl

Model studies were also carried out with several bisaryl substrates (4a-c) viz., perfluorobiphenyl (4a PFB), perfluoro-phenyl sulfide (4b PFPS) and perfluorobenzophenone (4c PFBP). 

Fluoro-l-halogeno- ElOb, 207 (20 —S02 —CF, F/Hal) Perfluoro-phenyl- ElOa, 231... 

In a 100-ml crimped vial, t-butyl 5-norbomene-2-carboxylate (17.5 mmol) and the Step 1 product (7.5 mmol) were dissolved in 40 ml of toluene and then sparged with nitrogen for 30 minutes. The mixture was next treated with the slow addition of freshly prepared bis(toluene)bis(perfluoro-phenyl) nickel (II) catalyst (0.5 mmol) in 10 ml of dry toluene and stirred overnight. The polymer was precipitated into hexane and filtered, and 3.5 g of white powder were isolated. 

Perfluorinated phenylcycloalkenes, e.g. 7, are formed by the reaction of trimethyl(perfluoro-phenyl)silane with perfluorocycloalkenes in the presence of cesium fluoride. The reaction affords the products of mono- and diphenylation chlorines remain unsubstituted, e.g. 8. 

In the course of nucleophilic substitution of vinyl fluoride in azamethines by the perfluoro-phenyl group using triinethyl(perfluorophenyl)silane, the geometry of the starting azaalkene remains unchanged, possibly indicating stereospecificity of this reaction. 

Peril uorophenyl)copper (4) is most conveniently prepared by metathesis of (perfluoro-phenyl)magnesium, lithium, or cadmium reagents with copper(I) halides. Rickc and co-workers have also prepared (perfluorophcnyl)copper by the reaction of pentafluoroiodo-benzene with highly activated copper generated by the reduction of copper(I) iodide with potassium in the presence of 10% naphthalene. Utilization of normal copper metal gives rise instead to decafluorobiphenyl and no (perfluorophenyl)copper is detected. (Perfluorophenyl)-copper is a stable, isolable material which decomposes above 200 "C to form decafluorobiphenyl and copper metal, and is hydrolyzed and oxidized slowly in moist air. 

In a limited number of cases, arylsilanes react with aldehydes as if they were aryl Grignard or aryllithium reagents. Both trimethyl(perchlorophenyl)silane and trimethyl(perfluoro-phenyl)silane react with benzaldehyde to give the corresponding 7.-(pcrhalophenyl)bcnzyl tri-methylsilyl ethers.163 Benzaldehyde reacts completely with trimethyl(perfluorophenyl)silane in diethyl ether in the presence of either a catalytic amount of the potassium cyanide/18-crown-6 complex in less than 5 hours at room temperature or potassium fluoride in dimethylform-umide.164 In the case of aryltrimcthylsilanes containing electron-withdrawing substituents in the ortho position, the reaction is observed only under the conditions of nucleophilic catalysis by potassium fluoride or cesium fluoride. 

An isocyanide complex, R2NC02Cu(CNBut) (31 R = Et, 1.4) was isolated from reaction of CuOBu, Et2NH, and CO2. Treatment of (31) with R X provide urethanes. Ability of Cu X to promote urethane formation from R2NH, CO2, and R X decreases in the sequence X = OBu > OAc > Cl the presence of a ligand (in particular NCR) is necessary. Formation of perfluoro-phenyl-Au and isocyanide and carbene complexes are given in Scheme 6. 

Doubts about the validity of the biradical intermediate arose when the single crystal x-ray structure of the bis(perfluoro-phenyl)tetramethyl-2-tetrazenezinc(II) was shown to be the following (25). 

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