3-Phenyl-2-butyl -toluenesulfonate

Another detectable example of internal return is afforded by the solvolysis of xo-norborriylbromobenzenesulfonate (XL) it racemizes from 40 to 240% faster than it produces bromobenzenesulfonic acid, yet both reactions are strictly first order. The racemization reaction is kinetically independent of bulk bromobenzenesulfonate concentration but its rate is dependent on the nature of the solvent, pyridine being less effective than alcohol, acetic acid, or aqueous acetone.238 The behavior of 3-phenyl-2-butyl- -toluenesulfonate is similar.250... 

Winstein provided powerful support for the phenonium ion hypothesis it 1952. He followed the rate of solvolysis of tAreo-3-phenyl-2-butyl tosylate botl titrametrically, by titrating the toluenesulfonic acid formed, and polarimetrically... 

Moreover, the formation of enoxy-silanes via silylation of ketones127 by means of N-methyl-N-TMS-acetamide (1 72) in presence of sodium trimethylsilanolate (173) was reported in 1969 and since then, the use of silylating reagents in presence of a catalyst has found wide appreciation and growing utilization as shown in recent papers128-132 (Scheme 27). Diacetyl (181) can be converted by trifluoromethylsul-fonic acid-TMS-ester (182) into 2,3-bis(trimethylsiloxy)-l, 3-butadiene (7treatment with ethyl TMS acetate (7 5)/tetrakis(n-butyl)amine fluoride l-trimethylsiloxy-2-methyl-styrene (i<56)130. Cyclohexanone reacts with the combination dimethyl-TMS-amine (18 7)/p-toluenesulfonic acid to 1-trimethylsiloxy-l-cyclohexene (iSS)131. Similarly, acetylacetone plus phenyl-triethylsilyl-sulfide (189) afford 2-triethylsiloxy-2-pentene-4-one (790)132. ... 

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... 

Benzene, iV AT-dimethylfcnmamide (DMF), dichlorometiiane, metiiyl methacrylate, tert-butyl methacrylate (TBMA) and p-terT-butoxystyrene (tBOSt) were purchased and distilled before use. 2,2 -Azobisisobutyronitrile (AIBN) was purified by recrystallization from etiianol. 9-Fluorenilideneimino p-toluenesulfonate (FITS) (72), neopentyl styrenesulfonate (NPSS) (73), cyclohexyl styrenesulfonate (CHSS) (14) and phenyl styrenesulfonate (PhSS) were prepared according to the lito ture. Qxone (potassium... 

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