Tosyl derivatives

Rearrangement of N.N-dimethyttiydrazone or tosylate derivatives of oxime to azirines and from there to a-amino ketones. 

Dissolve in Et20, dry over KOH and distil. The N-Tosyl derivative has m 134-135° (from EtOH). [Chem Ber 96 550 1963.]... 

The action of potassium thiocyanate on tosylates derived from fluorohydnns gives the corresponding fluonnated alkyl thiocyanates [43] (equation 39)... 

Diazomethane and 1 -substituted 1 //-azepine-4,5-dicarboxylates 44 yield the C4 — C5 pyrazoline adducts, e. g. 45.234 In contrast, the 1-mesyl and the 1-tosyl derivatives yield only adducts of the benzene imine valence tautomers of the l//-azepines. 

Dibenzo[l,3]diazepines 9, together with amidines and benzimidazoles, are produced by a rearrangement reaction when certain A.A -diarylamide oximes 7 are treated with tosyl chloride. The intermediate 0-tosyl derivatives 8 cannot be isolated.176... 

Triphenyl-2//-l,2,4-triazepine reacts with tosyl chloride under standard conditions to afford the 2-tosyl derivative 20.337... 

An entirely different approach to the synthesis of 2H-azirinecarboxylic esters involves a modified Neber reaction of oxime tosylates derived from -keto esters (Scheme 15) [26]. 

Tosylate derivatives are not usually found in nature, but sulfate derivatives of alcohols are common (52). They are formed by the reaction of an alcohol with sulfate, catalyzed by a sulfotransferase enzyme. 

Reaction of 5 -0-tosyl derivative 343 <1995ARS281> with an excess of ethylenediamine in refluxing acetonitrile afforded the hyper-modified tricyclic nucleoside 344 (28%) together with bicyclic nucleoside 345 (20%) and 4, 5 -dihydro nucleoside 346 (35%) (Scheme 73) <2003JOC6695>. 

An anhydro sugar which will probably find extensive synthetic use has been described by Hann and Hudson.85 This is the tricyclic compound, 3,4 1,6-dianhydro-jS-D-talopyranose (LXXIV) which is prepared by the saponification of the 4-tosyl derivative of mannosan (LXXIII). 

These workers also synthesized tryptamine stannane 161 and effected Stille couplings with this compound, including the intramolecular reaction 162 to 163 [171]. Eight- and 9-membered rings could also be fashioned in this manner. Other Pd catalysts were much less successful. The N-tosyl derivative of 162 was similarly prepared and used in Stille chemistry. 

The thermal cyclization of )V-[2-(disubstituted amino)phenyl]amino-methylenemalonates (568, R1 + H,R2 + H) by heating in boiling diphenyl ether for 5-18 min afforded quinolines (569, R1 + H, R2 =h H) in 53-81% yields [75JCS(P 1)2409]. 7V-[2-(Substituted amino)phenyl]aminomethy-lenemalonates (568, R + H, R2 = H) failed to cyclize to the corresponding quinolines (569, R1 + H, R2 = H) when heated in diphenyl ether, but their JV-(p-tosyl) derivatives (568, R2 = 4-MePhS02) gave the expected products (569, R2 = 4-MePhS02) in 72-77% yields. 

Compared with the sulphinimines, the A -tosylsulphinimines are less readily reduced and, to obtain acceptable yields, it is necessary to use larger amounts of catalyst. This suggests that the A-tosyl derivatives may be hydrolysed to the sulphinimines prior to the electrophilic attack by the carbene. 

Preparation of cyclodextrin derivatives substitution at a secondary hydroxyl group of the cyclodextrin annulus. Murakami and cowor-kers described a new and convenient method for the regioselective tosylation of the 2-hydroxyl groups of alpha, beta, and gamma cyclodextrin by means of a cyclic tin intermediate. The method is based on the reaction of dibutyltin oxide with 1,2-diols to form five-membered dibutyl-stannylidene derivatives. Useful yields of the 2-6>-tosyl derivatives of the cyclodextrins were obtained. 

D-galactosyl-(o -l,4-L-fucosyl)-iV-acetyl-D-glucos-aminyl-R. It can also act on the corresponding 1,4-galac-tosyl derivative, forming 1,3-L-fucosyl links. 

Thianthrene radical ion(l+) reacts with ammonia to produce salt 33 (X = S), alkaline hydrolysis of which afforded the sulfimine 34 (X = S, R = H) and thianthrene 5-oxide. The sulfimine was unstable in light, and hydrolyzed to the corresponding oxide by aqueous acid, but gave a stable 7V-tosyl derivative (34) (X = S, R = Ts) (72JA1026). 

The 1,3-dipolar cycloaddition reaction of nitrile sulfides with nitriles yields 3,5-disubstituted 1,2,4-thiadiazoles of unequivocal structure. This method has received considerable attention in recent years. Electron deficient nitriles such as tosyl cyanide afford high yields of 5-tosyl derivatives (341) (Equation (53) see also Scheme 61) <93JHC357). 

The formation of an A-tosyl derivative of a meso-ionic l,2-oxazol-4-imine (370) in solution is possible, but the product was not isolated. 

Amino-3,5-dimethylisoxazole (372, R = H) gave an iV-tosyl derivative (372, R = tosyl), which by treatment with methyl fluorosulfonate followed by perchloric acid gave the salt 371, R = R = R = Me, R = tosyl, X = C104. Attempts to isolate the meso-ionic sul-fonamidate (370, R = R = R = Me, R = tosyl) by treatment of the salt with potassium hydroxide or triethylamine were unsuccessful, but spectroscopic evidence for its formation in solution has been offered. 

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