Phenyl-p-toluenesulfonate

Aryl sulfonates RS03Ar (R = C6H5, CH3) were found to undergo photochemical rearrangement upon irradiation with uv-light.8,9 In the case of phenyl p-toluenesulfonate (20), products originating from the photo-Fries reaction were identified as 2-hydroxy-4 -methyldiphenyl sulfone (21), 4-hydroxy-4 -methyldiphenyl sulfone (22), and phenol (23). 

One can also start directly from p-pinene (142). This was opened to the nitro compound 599 with nitrous acid, titanium tetrachloride then giving perilla aldehyde (600). Photochemical addition of 5e-phenyl p-toluenesulfonate to P-pinene yielded an addition product in 91% yield, oxidative deselenylation of which gave 94% of the 7-substituted menthadiene 601, but the latter was not converted to the oxygenated menthadiene. ... 

CH2CH2C02CH2Ph l-Ethyl-3-phenyl p-toluenesulfonate l-(2-Dimethylaminoethyl)-2,3-diphenyl chloride hydrochloride Hemiethanolate... 

The coupling of anions derived from phenyl p-toluenesulfonate, N-methyl-p-toluenesulfonanilide or their o-isomers represents another modification of a chain process involving electron transfer. Scheme 18 has been suggested (Lu and Truce, 1985). The sequence of steps in Scheme 18 is... 

Oxazoles have attracted considerable interest due their presence as subunits of several biologically active compoimds or as rigid mimetics of a peptidic ring. A first synthesis of 2-phenyl-4,5-substituted oxazoles 54 [47] was described by microwave-assisted reaction of enolizable ketones with benzoni-trile in the presence of mercury(II) p-toluenesulfonate (Scheme 17). 

CN [3-[[4-(3-ethoxy-2-hydroxypropoxy)phenyl]amino]-3-oxopropyl]dimethylsulfonium p-toluenesulfonate... 

Pyrazolo-[3,4i>]-quinolines and -pyrazoles have been synthesized by reacting [i-chlorovinylaldehydes and hydrazine or phenyl hydrazine using a catalytic amount of p-toluenesulfonic acid (PTSA) under the action of microwave irradiation. The yields are much better than under the action of A using the same conditions [105] (Eq. 55). 

Sardesai and Sunthankar studied the cyclization of diethyl )V-(2-amino-phenyl)aminomethylenemalonate (162, R = H) (57MI2 59MI1). No cyclization occurred in refluxing xylene in the presence or absence of a catalyst (p-toluenesulfonic acid or sodium hydroxide), or in acetic anhydride, or in a mixture of acetic anhydride and concentrated sulfuric acid. Benzimidazole and benzimidazolone were obtained in 20% and 66% yields, respectively, when 162 (R = H) was distilled in vacuo. Benzimidazolone was the product when 162 (R = H) was heated in boiling diphenyl ether, o-Phenylenediamine was reacted with diethyl acetylmalonate at 140°C for 4 hr to give 2-methylbenzimidazole and diethyl malonate (85S555). 

As found by Engman et al. (1999), sodium alkyltelluroates are excellent reagents for the generation of aryl radicals from the corresponding iodides in the dark. Accordingly, l-(2-iodo-phenyl)-l-methyloxirane reacts with two equivalents of sodium 1-butyltelluroate giving 2,3-dihydro-3-hydroxy-3-methylbenzo[( ]tellurophene, which was isolated in 62% yield. The latter was readily converted into 2,3-dihydro-3-methylbenzo[( ]tellurophene on treatment with a catalytic amount of p-toluenesulfonic acid (94% yield Scheme 7.42). 

Similarly, lithium aluminum hydride gives different products. / -Naphthyl p-toluenesulfonate affords p-thiocresol and ) -naphthol, and phenyl meth-anesulfonate gives methyl mercaptan and phenol. On the other hand, propyl p-toluenesulfonate yields />-toluenesulfonic acid and propane, and cetyl meth-anesulfonate and cetyl p-toluenesulfonate give hexadecane in 92% and 96% yields, respectively [680]. 

PENTAMETHYL-, 56, 1 Cyctopentane, acetyl-, 55, 25 Cyclopentane, 1-cyano-l-phenyl-, 55, 94 Cyclopentane, methyl, 55, 62 Cyclopentanol p-toluenesulfonate, 55, 112 Cyclopentene, 56, 34, 58, 73 2-Cyclopenten-l-one, 2,5-dialkyl- 58, 62 CYCLOPENTENONES, 58, 56 Cyclopropane, 1 -acetyl-1 -phenyl-, 55, 94 Cyclopropane, 1, l-dibromo-2,2-diphenyl-, 56, 32... 

Treatment of 107 with 75 in the presence of 0.15-0.45 mol. equivalent of p-toluenesulfonic acid for 40 - 50 h at room temperature gave60 the (5RS)-5-[(RS)-dimethoxyphosphinyl]-5-(p-tolylsulfonylhydrazino)hexo-furanoses 108 (70% yield). Likewise, compound 107 and methyl phenyl-phosphinate gave an 100% yield of the 5-[(methoxy)phenylphos-phinyl] compound 109, whereas hydrazone 106 afforded four products, namely, two isomers of the xylofuranoses 110 (15%) and two isomers of the 5-C-[(RS)-(0,P-anhydro)phenylphosphinyl] derivatives 111 (51 and 26%). Compound 111 was considered to be produced from 110 during isolation employing sodium hydrogencarbonate, because 110 readily afforded 111 by treatment with sodium methoxide. 

The treatment of furfuryl phenyl selenides (178) with n-butyllithium or metallic lithium affords furfuryllithium reagents which undergo ring opening to furnish initially the allenic ketones (180) (80TL3209). Two equivalents of n-butyllithium are required for complete conversion due to the acidic character of the allenic hydrogen. The allenic ketones are readily isomerized to the dienones (181) on p-toluenesulfonic acid treatment (Scheme 38). 

Heating a mixture of 2-(carboxymethyl)benzoic acids and 3-amino-propanol in o-dichlorobenzene in the presence of p-toluenesulfonic acid yielded 2,3,4,6-tetrahydro[l,3]oxazino[3,2-b]isoquinolin-6-ones (78BEP 866987, 78GEP2756067 79CPB2372). Similar reaction between o-benzoylphenylacetic acid and 3-aminopropanol in toluene resulted in 11 b-phenyl-2,3,4,6,7,116-hexahydro[l,3]oxazino[2,3-a]isoquinolin-6-one (71MI1). Reaction of 2-(2-bromoethyl)benzaldehyde and 3-aminopropanol in ethanol led to 2,3,4,6,7,llb-hexahydro[l,3]oxazino[2,3-a]isoquinoline (61AP645). 

Reaction of 4-phenyl-6-chloro-2(lH)-pyridone and 3-aminopropanethiol on heating in ethylene glycol at 190-200°C afforded 8-phenyl 2,3, 4,6-tetrahydropyrido[2,l-6][l,3]thiazin-6-one (79CPB1207). 2,3,4,6,7,116-Hexahydro[l,3]thiazino[2,3-a]isoquinolin-4-ones (204) were obtained in the reactions of 3,4-dihydroisoquinolines and 3-mercaptopropionic acid in the presence of p-toluenesulfonic acid (69FRP155211 87MI1). 

Table 2.2. lists activators used less commonly for Moffatt oxidations. The following activators, namely diphosgene,262 triphosgene,263 2-chloro-1,3-dimethylimidazolinium chloride,264 l-cyclohexyl-3-(2-morpholinoethyl)-carbodiimide metho-p-toluenesulfonate,265 triphenylphosphine dibromide and dichloride,266 and phenyl dichlorophosphate,267 have been the subject of scientific monographs, in which they are proposed as suitable and convenient alternatives to more routinely used activators, and can offer improved oxidation conditions in some substrates. 

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. ... 

Benzaldehyde dimethylacetal (200 pi, 1.33 mmol) and a catalytic amount of p-toluenesulfonic acid (37 mg) are added to methyl (2R,3S)-3-(4-nitrobenzenesulfonamido)-3-phenyl-2-hydroxypropionate (315 mg, 0.83 mmol) in toluene 5 ml. The mixture is heated at 100°C under reduced pressure (15 mm mercury) with no condenser. After 1 h the crude reaction mixture is diluted with ethyl acetate and washed with water (2 times). After drying the organic layer over magnesium sulfate the crude material is purified by column chormatography (silica gel eluting with ethyl acetate/cyclohexane, 35/65) to give the (2S,4S,5R)-2,4-diphenyl-3-(4-nitrobenzenesulfonamido)-5-methoxycarbonyl-l,3-oxazolidine, melting point 118°-120°C. 

Helferich10 10 and co-workers prepared phenyl /J-D-fructopyranoside, m. p. 173°, [ ]D —210° in water and o-cresyl /J-D-fructopyranoside, m. p. 167-170°, [o]D —233° in water, by the deacetylation of the products obtained by heating /3-D-fructopyranose pentaacetate with phenol and o-cresol, respectively, in the presence of p-toluenesulfonic acid. 

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