P-Toluenesulfonyl fluoride

An efficient and inexpensive method for the substitution of an allylic hydroxyl group with fluorine, without allylic rearrangement and elimination consists of treating an allylic alcohol with methyllithium followed by p-toluenesulfonyl fluoride, lithium fluoride and 12-crown-4.6 By this method, geranyl fluoride, neryl fluoride, cinnamyl fluoride, ( , )-farnesyl fluoride, retinyl fluoride and 4-fluoro-2-methyl-6-(4-tolyl)hept-2-ene are prepared. 

Benzyl and alky] trialkylsilyl ethers undergo clean fluorination to give good yields of benzyl and alkyl fluorides, respectively, when reacted with a combination of a quaternary ammonium fluoride and methanesulfonyl o r p- toluenesulfonyl fluoride. The reactions are applicable strictly to a primary carbon-oxygen bond, secondary and tertiary alkyl silyl ethers remain intact or, under forcing conditions, are dehydrated to olefins [29] (equation 22)... 

Preparative Methods generated by deprotonation of the triphenyl(p-toluenesulfonyl)methylphosphonium halide salts, which can be prepared by heating of bromomethyl p-tolyl sulfone and triphenylphosphine or by treatment of p-toluenesulfonyl fluoride with methylenetriphenylphosphorane (eq 1). 

An ethereal soln. of p-toluenesulfonyl fluoride added dropwise to ethylmagne-sium bromide prepared from ethyl bromide and Mg in ether, refluxed 13-15 hrs. 

Cesium fluoride, 68 Sulfonic acids and esters p-Toluenesulfonate esters p-Toluenesulfonyl chloride, 313 Trifluoromethanesulfonate esters N-Phenyltrifluoromethanesulfonimide, 142... 

NMO NMP Nu PPA PCC PDC phen Phth PPE PPTS Red-Al SEM Sia2BH TAS TBAF TBDMS TBDMS-C1 TBHP TCE TCNE TES Tf TFA TFAA THF THP TIPBS-C1 TIPS-C1 TMEDA TMS TMS-C1 TMS-CN Tol TosMIC TPP Tr Ts TTFA TTN N-methylmorpholine N-oxide jV-methyl-2-pyrrolidone nucleophile polyphosphoric acid pyridinium chlorochromate pyridinium dichromate 1,10-phenanthroline phthaloyl polyphosphate ester pyridinium p-toluenesulfonate sodium bis(methoxyethoxy)aluminum dihydride (3-trimethylsilylethoxy methyl disiamylborane tris(diethylamino)sulfonium tetra-n-butylammonium fluoride f-butyldimethylsilyl f-butyldimethylsilyl chloride f-butyl hydroperoxide 2,2,2-trichloroethanol tetracyanoethylene triethylsilyl triflyl (trifluoromethanesulfonyl) trifluoroacetic acid trifluoroacetic anhydride tetrahydrofuran tetrahydropyranyl 2,4,6-triisopropylbenzenesulfonyl chloride 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane tetramethylethylenediamine [ 1,2-bis(dimethylamino)ethane] trimethylsilyl trimethylsilyl chloride trimethylsilyl cyanide tolyl tosylmethyl isocyanide meso-tetraphenylporphyrin trityl (triphenylmethyl) tosyl (p-toluenesulfonyl) thallium trifluoroacetate thallium(III) nitrate... 

The first application of copper(I)-catalyzed 1,3-dipolar cycloaddition in preparation of [18F]fluoropeptides was reported by Marik and Sutcliffe in 2006 (Figure 14.9) [92]. Three [18F]fluoroalkynes (n = 1, 2, and 3) were prepared in yields ranging from 36% to 80% by nucleophilic substitution of a p-toluenesulfonyl moiety with [18F]fluoride ion. Reaction of these [18F]fluoroalkynes with various peptides (previously derivatized with 3-azidopropionic acid) via the Cu(I)-mediated 1,3-dipolar cycloaddition provided the desired 18F-labeled peptides in 10 minutes at room temperature with yields of 54-99% and great radiochemical purity (81-99%) [82]. 

Phenylmethanesulfonyl fluoride was chosen for the first step because the phenylmethanesulfonyl group is a better leaving group in the SN2 displacement of the second step than the p-toluenesulfonyl group,... 

Scheme 11.49. A synthesis of periplanone A (after Hauptmann, H. Mtlhlbauer, G. Sass, H. Tetrahedron Lett., 1986, 6189). LDA = lithium diisopropyl amide p-TsCl = para-toluenesulfonyl chloride NaHMDS = sodium hexamethyldisilazide DMAP = 4-dimethyl-aminopyridine TMSCl = trimethylchlorosilane PCC = pyridiniumchlorochromate TBHP = f-butyl hydrogen peroxide TBDMSCI = f-butyldimethylchlorosilane TBAF = tetrabutylammonium fluoride Cp = cyclopentenyl.

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