Methyl p-toluenesulfonate

It is known that the [Ni(I)(OEiBC)] complex mediates electrocatalytic reductions of alkyl halides and methyl p-toluenesulfonate [305]. The nucleophilic-ity of the Ni(I) complex is comparable to that of the supernucleophile vitamin Bi2. Recently, the formation of... 

Alkylation of 125,6,8,47 and 6747 gives the mono-N-alkyl cations in good to excellent yields. Generally the iodide has been used, but chlorides and bromides also apparently form salts at high temperatures prior to rearrangement.7 With methyl p-toluenesulfonate, compounds 23 form the corresponding 2-methyl cations.33... 

The bis(triazolopyrimidyl)methanes 39 were quaternized with methyl p-toluenesulfonate to give 254, whose treatment with base gave the mesoionic methine dyes 255 (82UKZ79). The methylene group of 39 was active to be condensed with aldehydes (Scheme 48). 

Fig. 4.—Ultraviolet Absorption Spectrum1 t of Methyl p-Toluenesulfonate (in Hexane).

When instead of the adds, alkyl halides or methyl p-toluenesulfonate were used as the initiator, the dimerization reaction stopped at the N-alkyl piperazinium salt stage (38). Hem also, dimer formation is favored in acetone while solvents of high polarity and solvating power tend to favor polymer formation. 

A similar series of reactions was carried out with 7-azaindole. The 7-methyl salt (111) was obtained in quantitative yield as the iodide (111, X = I) by allowing 7-azaindole to stand with methyl iodide at room temperature for 4 days. Methyl p-toluenesulfonate in... 

SYNS METHYLESTER KYSELINY p-TOLUEN-SULFONOVE (CZECH) METHYL-4-METHYLBENZ-ENESULFONATE METHYL-p-TOLUENESULFONATE METHYL TOLUENE-4-SULFONATE D METHYL TOS i LATE METHYL-p-TOS i LATE p-TOLUOL-SULFONSAEURE METHYL ESTER (GERMAN)... 

The core-first method, which uses an active multifimctional core to initiate growth of polymer chains, was apphcable to make hybrid POSS-core star-shaped polyoxazohnes that showed an increase in Tg, compared to that of polyoxazohne initiated by methyl p-toluenesulfonate (MeOTs) with poly(2-methyl-2-oxazohne) (POZO) [76]. Other hybrid star-shaped polyoxazohnes initiated by cube-OTs or cube-benzyl revealed the same phenomenon. This was attributed to the reduction of segmental mobifity of POZO in starshaped polyoxazolines, which was caused by the incorporation of hard, compact POSS moiety to the core of star polymer with the core-first technique. The conclusions were drawn that the thermal stabilities of star-shaped polymers increased as the POSS wt % was increased, and this was used as a measure of the effect of the inorganic POSS unit on polymer thermal properties. 

Under acidic or neutral conditions methylation of xanthine proceeds at N-7 or N-9. Thus with methyl iodide the 7,9-dimethylxanthine betaine (107) results after heating in a sealed tube at 150 °C for 5 h. In solvents such ag DMSO or dimethylacetamide using dimethyl sulfate or methyl p-toluenesulfonate, better yields may be obtained (62CB1812). The same betaine is also produced by similar methylation of 9-methylxanthine (62JA1914,61LA(647)l6l). 

Three patents have been issued in which two novel methods for forming sulfonic esters are described. A water-soluble derivative, sodium mono-0-(propylsulfonyl)rutin, was prepared by sequential treatment of rutin with sodium in ethanol, followed by propane sul-tone in N,N-dimethylformamide. The second method employed methyl p-toluenesulfonate in N,N-dimethylformamide, with potassium carbonate as a catalyst, for transesterification of the hemiacetal group of aldoses or ketoses. 

Well-mixed A -alkyl- or iV-aryl-6-nitroquinazolin-4-amine (0.1 mol) and methyl p-toluenesulfonate (0.11 mol) in anhyd nitrobenzene (140 mL) was healed at 170 °C for 0.5 h. Partial solution was obtained before the quaternary salt separated. After the mixture had cooled to 20 C, the respective quina/.oliniutn p-toluenesulfonate was filtered off and washed with acetone. 

Reaction of quinoxaline with iodoethane in refluxing acetonitrile gives ethyl quinoxalini-um iodide, and treatment of the parent base with methyl p-toluenesulfonate gives methyl quinoxalinium jt -toluenesulfonate in a high yield. ... 

Not surprisingly, if the ketone in the starting material is flanked by an unsaturated functional group i.e. C02Me or NO ), dehydration gives exclusively the a,P-unsaturated product (the p,y-unsaturated regioisomer is available via other methods, discussed below). While the methods described above involve direct dehydration of the alcohol, a number of reduction-dehydration sequences have been conducted by initial reduction of the ketone and subsequent derivatization of the resultant alcohol (as the phenyl methanesulfonate, methyl p-toluenesulfonate, xanthate, acetate, methyl ether, etc.). This type of reduction-dehydration sequence is discussed in detail in Volume 6, Chapter 5.1. 

Methylation of a cyclopropyl sulfide occurred on reaction of 1-methylsulfanylcyclopropane- rani-l,2-dicarboxylic acid with methyl p-toluenesulfonate in formic acid. ° ... 

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