Tosyl, abbreviation

The sulfonate esters used most frequently are the p toluenesulfonates They are com monly known as tosylates abbreviated as ROTs... 

Alkyl chlorides, bromides and iodides can be formed by the reaction of alcohols with p-toluenesulfonyl chloride (or tosyl chloride, abbreviated as TsCl) in the presence of a nitrogen base (e.g. triethylamine or pyridine). The OH group is converted into a tosylate (abbreviated as ROTs), which can be displaced on reaction with CF, BF or I-. The stable tosylate anion is an excellent leaving group (SN1 or SN2 mechanism depending on the nature of the alkyl group, R). 

Several sulfonyl chlorides are available to activate OH groups. The most common one is para-toluenesulfonyl chloride (abbreviated as TsCl). The sulfonate ester formed from the reaction of TsCl and an alcohol is called an alkyl tosylate (abbreviated as ROTs). 

Abbreviations aapy, 2-acetamidopyridine Aik, alkyl AN, acetoniuile Ar, aryl Bu, butyl cod, 1,5-cyclooctadiene COE, cyclooctene COT, cyclooctatetraene Cp, cyclopentadienyl Cp , penta-methylcyclopentadienyl Cy, cyclohexyl DME, 1,2-dimethoxyethane DME, dimethylformamide DMSO, dimethyl sulfoxide dmpe, dimethylphosphinoethane dppe, diphenylphosphinoethane dppm, diphenylphosphinomethane dppp, diphenylphosphinopropane Et, ethyl Ec, feirocenyl ind, inda-zolyl Me, methyl Mes, mesitylene nb, norbomene orbicyclo[2.2.1]heptene nbd, 2,5-norbomadiene OTf, uiflate Ph, phenyl PPN, bis(triphenylphosphoranylidene)ammonium Pi , propyl py, pyridine pz, pyrazolate pz, substituted pyi azolate pz , 3,5-dimethylpyrazolate quin, quinolin-8-olate solv, solvent tfb, teti afluorobenzobaiTelene THE, tetrahydrofuran THT, tetrahydrothiophene tmeda, teti amethylethylenediamine Tol, tolyl Tp, HB(C3H3N2)3 Tp , HB(3,5-Me2C3HN2)3 Tp, substituted hydrotiis(pyrazol-l-yl)borate Ts, tosyl tz, 1,2,4-triazolate Vin, vinyl. 

The following abbreviations are commonly used for substituent groups in structural formulae Ac (acetyl), Bn or PhCH2 (benzyl), Bz or PhCO (benzoyl), Et (ethyl), Me (methyl), Me3Si (not TMS) (trimethylsilyl), Bu Me2Si (not TBDMS) (rerf-butyldimethylsilyl), Ph (phenyl), Tf (triflyl = trifluoromethanesulfonyl), Ts (tosyl = toluene-p-sulfonyl), Tr (trityl). 

Abbreviations IMP, 2,4,6-trimethylpyridinium fluoride FMPTs, 2-fluoro-l-methylpyridinium tosylate Ishikawa, Ishikawa reagent (Ref. 74) Mitsunobu, through Mitsunobu reaction (Ref. 80) NBS, A-bromosuccinimide Piv, pivaloyl and Py, pyridine. 

Abbreviations for methanesulfonyl chloride and /7-toluenesulfonyl chloride are mesyl chloride and tosyl chloride , respectively. 

Section 7.8). Other classes of derivatives are thus most conveniently prepared from the sulfonyl chloride. Reaction with an alcohol leads to formation of a sulfonate ester. Two common sulfonyl chloride reagents employed to make sulfonate esters from alcohols arep-toluenesulfonyl chloride, known as tosyl chloride, and methanesulfonyl chloride, known as mesyl chloride (see Section 6.1.4). Note the nomenclature tosyl and mesyl for these groups, which may be abbreviated to Ts and Ms respectively. 

The following abbreviations are used in this and the subsequent tables Ac for acetyl, Pr for propionyl, Bu for butyryl, Bz for benzoyl, Ts for tosyl, My for methylene, Ed for ethylidene, Bd for benzylidene, Fd for furfurylidene. Id for isopropylidene, Me for methyl, Et for ethyl, Be for benzyl, Tr for trityl and Az for azoyl. Where the linkages of acetals and ketals are known, they are shown by different type fonts.)... 

As in part (a), identify the nucleophilic anion in each part. The nucleophile replaces the p-toluene-sulfonate (tosylate) leaving group by an SN2 process. The tosylate group is abbreviated as OTs. 

Fig. 10.5. Notable examples of Rcelp inhibitors. Abbreviations shown refer to At,-tosyl-l-phenylalanine chloromethyl ketone (TPCK), p-hydroxymercnribenzoic acid (pHMB), p-hydroxymercuriphenylsulfonic acid (pHMS), mersalyl acid (MSA), (acyloxy)methyl ketone (AOMK), and National Service Center (NSC).

An alkyl tosylate is composed of two parts the alkyl group R, derived from an alcohol and the tosylate (short for p-toluenesulfonate), which is a good leaving group. A tosyl group, CH3C6H4S02 , is abbreviated as Ts, so an alkyl tosylate becomes ROTs. 

Recall from Section 9.13 that CH3C6H4SO2- is called a tosyl group, abbreviated by the letters Ts. For this reason, p-toluenesulfonic acid (also called tosic acid) is abbreviated as TsOH. 

Alkyl tosylate (Section 9.13) A compound having the general structure ROSO2C6H4CH3. Alkyl tosylates are also called tosylates and are abbreviated as ROTs. 

Abbreviations Ac acetyl AIBN azobisisobutyronitrile All allyl Bn benzyl Bz benzoyl ClAc chloroacetyl DAST diethylaminosulfur trifluoride DBU l,8-diazabicyclo[5.4.0]-undec-7-ene DDQ 2,3-dichloro-5,6-dicyano-/)-benzoquinone DMDO dimethyldioxirane DMTST dimethyl(methylthio)sulfonium trifluoromethanesulfonate Fmoc 9-fluorenyl-methoxycarbonyl HDTC hydrazine dithiocarboxylate IDCP iodonium di-collidine perchlorate Lev levulinoyl MBz 4-methylbenzoyl Me methyl MEK methyl ethyl ketone MP 4-methoxyphenyl NBS iV-bromosuccinimide NIS A-iodosuccinimide Pent n-pentenyl Pfp pentafluorophenyl Ph phenyl Phth phthaloyl Piv pivaloyl PMB 4-methoxybenzyl TBAF tetrabutylammonium fluoride TBDMS tcrt-butyldimethylsilyl TBDPS tert-butyldiphenylsilyl TCA trichloroacetyl TES triethylsilyl Tf trifluoromethanesulfonyl TMS trimethylsilyl Tol 4-methylphenyl Tr trityl Troc 2,2,2-trichloroethoxycarbonyl Ts tosyl. 

Abbreviations are often used for monovalent groups that commonly appear in organic compounds. Some of these abbreviations are shown in Table 1.1. Aryl may be phenyl, a substituted phenyl, or a heteroaromatic group like furyl, pyridyl, or pyrrolyl. Tosyl is shorthand for p-toluenesulfonyl, mesyl is shorthand for methanesul louyi, and triflyl is shorthand for trifluoromethanesulfonvl. TsO, MsO-, and TI O are abbreviations for the common leaving groups tosylate, mesylate, and triflate, respectively. 

Starting with 3,5-dibenzoyl-2-deoxy-D-ribose, Marriott and Bantick developed an abbreviated synthesis of Corey s tosylate intermediate, 67 (Scheme 3.26). Their sequence is similar to that shown in Scheme 3.25, but by starting with the deoxy sugar there is of course no need to remove the oxygen function, nor was it necessary to acetylate the hydroxyl group as in 66, thus eliminating a protection/deprotection sequence. 

The way they solved the problem was this. (S )-(-)-Malic acid is available cheaply. Its dimethyl ester 127 could be chemoselectively reduced by borane to give 128. Normally borane does not reduce esters and clearly the borane first reacts with the OH group and then delivers hydride to the nearer carbonyl group. The primary alcohol was chemoselectively tosylated 129 and the remaining (secondary) OH protected with a silyl group 130 (TBDMS stands for t-butyldimethylsilyl and is sometimes abbreviated to TBS). Now the remaining ester can be reduced to an aldehyde 131 and protected 132. Displacement of tosylate by cyanide puts in the extra carbon atom 133 and reduction gives 134, that is the dialdehyde 126 in which one of the two aldehydes is protected. This compound was used in the successful synthesis of lipstatin. 

R, R and R are alkyl groups. The structure marked t is sometimes abbreviated to R—OTs, short for tosylate. 

The pura-toluenesulfonate ester group (often abbreviated to tosylate, or OTs and shown in Figure 3.5) is also a good leaving group (the acid dissociation constant of CH3C6H4SO3H is 10 ), and so Sn reactions are possible (for example. Reaction 3.6)... 

The p-toluenesulfonate group is commonly referred to as tosylate and abbreviated -OTs.)... 

With regard to the reaction above (5A.42), recall the abbreviation Ts = tosyl or p-toluenesulfonyl (i.e., P-CH3-C6H4-SO2-). The hydrazones (as the products with hydrazine are called) lend themselves to a number of unique transformations, of which we will discuss the Wolff-Kishner reduction and the Shapiro reaction. 

Two of the most commonly used sulfonyl chlorides are p-toluenesulfonyl chloride (abbreviated tosyl chloride, TsCl) and methanesulfonyl chloride (abbreviated mesyl chloride, MsCl). Treating ethanol with p-toluenesulfonyl chloride in the presence of pyridine gives ethyl p-toluenesulfonate (ethyl tosylate). Pyridine is added to catalyze the reaction and to neutralize the HCl formed as a by-producf. Cyclohexanol is converted to cyclohexyl methanesulfonate (cyclohexyl mesylate) by a similar reaction of cyclohexanol with methanesulfonyl chloride. 

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