Pyridine, 4-benzyl-, nitration

A similar (but somewhat less obvious) dichotomy results in the simultaneous ring and sidechain substitution of durene. Thus in this charge-transfer nitration, the addition of N02 to the cation radical DUR+- (72) occurs in competition with its deprotonation (73), in which the pyridine has been shown to act as a base (Masnovi et al., 1989) (Scheme 15). [Note that deprotonation of DUR+- also leads to aromatic dimers via the subsequent (oxidative) substitution of the benzylic radical formed in (73) (Bewick et al., 1975 Lau and Kochi, 1984).]... 

Other reagents that convert benzylic halides to aldehydes are 2-nitropropane-NaOEt in EtOH,336 mercury(I) nitrate followed by ethanolic alkali,337 and pyridine followed by p-nitrosodimethylaniline and then water. The last procedure is called the Krohnke reaction. Primary halides in general have been oxidized to aldehydes by trimethylamine oxide,338 by... 

Ac, acetyl AIBN, azobis(isobutanonitrile) All, allyl AR, aryl Bn, benzyl f-BOC, ferf-butoxycarbonyl Bu, Butyl Bz, benzoyl CAN, ceric ammonium nitrate Cbz, benzyloxycarbonyl m-CPBA, m-chloroperoxybenzoic acid DAST, diethylaminosulfur trifluoride DBU, l,8-diazabicyclo[5.4.0]undec-7-ene DCC, /V. /V - d i eye I oh e x y I c ar bo -diimide DCM, dichloromethyl DCMME, dichloromethyl methyl ether DDQ, 2,3-dichloro-5,6-dicyano-l,4-benzoquinone DEAD, diethyl azodicarboxylate l-(+)-DET, L-(+)-diethyl tartrate l-DIPT, L-diisopropyl tartrate d-DIPT, D-diisopropyl tartrate DMAP, 4-dimethylaminopyridine DME, 1,2-dimethoxyethane DMF, /V./V-dimethylformamide DMP, 2,2-dimethoxypropane Et, ethyl Im, imidazole KHMDS, potassium hexamethyldisilazane Me, methyl Me2SO, dimethyl sulfoxide MOM, methoxymethyl MOMC1, methoxymethyl chloride Ms, methylsulfonyl MS, molecular sieves NBS, N-bromosuccinimide NIS, /V-iodosuccinimide NMO, /V-methylmorpho-line N-oxide PCC, pyridinium chlorochromate Ph, phenyl PMB, / -methoxvbenzyl PPTs, pyridiniump-toluenesulfonate i-Pr, isopropyl Py, pyridine rt, room temperature TBAF, tetrabutylammonium fluoride TBS, ferf-butyl dimethylsilyl TBDMSC1, f-butylchlorodimethylsilane Tf, trifhioromethylsulfonyl Tf20, trifluoromethylsulfonic anhydride TFA, trifluoroacetic acid THF, tetrahydrofuran TMS, trimethylsilyl TPAP, tetra-n-propylammonium perruthenate / -TsOH. / -toluenesulfonic acid... 

Silver dichromate-pyridine complex (tetrapyridine silver dichromate), Ag2Cr207 4C5H5N, an orange-yellow solid prepared by adding a warm solution of potassium dichromate to a solution of silver nitrate in water and pyridine, oxidizes allylic and benzylic alcohols to aldehydes and acyl-tiins to a-diketones [659]. 

Ceric ammonium nitrate in water or in 50% acetic acid oxidizes ben-zylic alcohols at 90 °C in very good yields [420]. Only catalytic amounts of the reagent and sodium bromate as a reoxidant are needed to convert benzyl alcohol into benzaldehyde in 90% yield on heating in acetonitrile at 80 °C [421]. A similar result is obtained on treatment of benzyl alcohol with lead tetraacetate in pyridine at room temperature for a few hours (yield 85%) [442]. 

Benzylpiperidine 2-Benzyl pyridine 4-Biphenylcarboxaldehyde Bismuth nitrate Bromine... 

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