5-tolyl-2-norbornene

When norbornadiene is allowed to react under the influence of a nickel catalyst in amine, 5-tolyl-2-norbornene 93 is formed [113]. After dimerization of norbornadiene, (3-carbon elimination occurs to open the norbornane ring of 92. An analogous cleavage of a norbornane ring was observed in the palladium-catalyzed reaction of bromobenzene with norbornene [114]. 

Norbornenes possess a rigid bicyclic skeleton with structural strain, and thus undergo various unique reactions involving C-C bond cleavage. For example, dimerization of norbornadiene in an exo/exo mode was induced by a nickel catalyst to form 5-tolyl-2-norbornene (Scheme 7.5) [6]. The following mechanism is proposed oxidative cyclization of two norbornenes occurs on nickelfO) to... 

The silylation of benzylic G-H bonds is achieved by using Ru3(GO)12 catalyst in the presence of norbornene as a hydrogen acceptor.145 The reaction of 2-(2,6-dimethylphenyl)pyridine with triethylsilane in the presence of Ru3(CO)i2 catalyst and norbornene affords mono- and disilylation products in 30% and 55% yields, respectively (Equation (106)). The reaction of 2-(2-tolyl)pyridine shows that the silylation of the aromatic C-H bond is more facile than that of the benzylic C-H bond. 

Abbreviations aapy, 2-acetamidopyridine Aik, alkyl AN, acetonitrile Ar, aryl Bu, butyl cod, 1,5-cyclooctadiene COE, cyclooctene COT, cyclooctatetraene Cp, cyclopentadienyl Cp, penta-methylcyclopentadienyl Cy, cyclohexyl DME, 1,2-dimethoxyethane DMF, dimethylfonnaniide DMSO, dimethyl sulfoxide dmpe, dimethylphosphinoethane dppe, diphenylphosphinoethane dppm, diphenylphosphinomethane dppp, diphenylphosphinopropane Et, ethyl Fc, fetrocenyl ind, inda-zolyl Me, methyl Mes, mesitylene nb, norbornene or bicyclo[2.2.1 ]heptene nbd, 2,5-norbomadiene OTf, triflate Ph, phenyl PPN, bis(triphenylphosphoranylidene)ammonium Pr, propyl py, pyridine pz, pyrazolate pz, substimted pyrazolate pz, 3,5-dimethylpyrazolate quin, quinolin-8-olate solv, solvent tfb, tetrafluorobenzobatrelene THE, tetrahydrofuran THT, tetrahydrothiophene tmeda, tetramethylethylenediamine Tol, tolyl Tp, HB(C3H3N2)3 Tp, HB(3,5-Me2C3HN2)3 Tp, substituted hydrotris(pyrazol-l-yl)borate Ts, tosyl tz, 1,2,4-triazolate Vin, vinyl. 

Ethylhexyl)-2-cyano-3,3-diphenylacrylate, 194 2-Ethylhexyl diphenyl phosphate, 17, 76 2-Ethylhexyl di(p-tolyl)phosphate, 76 Ethylidene norbornene, 222 Ficin, 148... 

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