Toluene sulphon chloride

The acid crystallises in pale yellow prisms, which do not melt on heating, but explode. It is soluble in alcohol, acetone, acetic add, and ethyl acetate, fairly soluble in hot water, sparingly soluble in cold water. The disodium salt is orange and has a neutral reaction in water, whilst the trisodium salt is alkaline to litmus and neutral to phenolphthaldn. The add condenses with p-toluene sulphonic chloride in alkaline solution, yielding glistening plates, M.pt. 171° C. 

By means of this last reaction and using in one case benzene sulphon chloride and toluene, and in the second case toluene sulphon chloride and benzene, exactly the same phenyl tolyl sulphone is formed. 

A) Toluene -sulphonates. For directions, using an acetone solution of toluene-/) Sulphonyl chloride, see p. 249 use o 3-o 5 g. of the phenol. Note that the chloride should be dissolved in a minimum of acetone, otherwise separation of the ester may be slow and incomplete. 

The sulphonation of toluene at 100-120° results in the formation of p-toluene-sulphonic acid as the chief product, accompanied by small amounts of the ortho and meta isomers these are easily removed by crystallisation in the presence of sodium chloride. Sulphonation of naphthalene at about 160° 3uelds largely the p-sulphonic acid at lower temperatures (0-60°) the a-siil-phonic acid is produced almost exclusively. 

A number of basic materials such as hydroxides, hydrides and amides of alkaline and alkaline earth metals and metal oxides such as zinc oxide and antimony oxide are useful catalysts for the reaction. Acid ester-exchange catalysts such as boric acid, p-toluene sulphonic acid and zinc chloride are less... 

Aryl glycosides of 2-amino-2-deoxy sugars, as might be expected, can be prepared by similar techniques as was illustrated by the synthesis of phenyl 3,4,6-tri-0-acetyl-2-acetamido-2-deoxy-p-D-glucoside and -D-galactoside by toluene -sulphonic acid catalysed reactions between phenol and the hexosamine penta-acetates These products were then anomerised using zinc chloride as catalyst to provide means of obtaining -anomers. 

Dihydrocarvone [l] was treated with isopropenyl acetate in the presence of p-toluene sulphonic acid and converted into a mixture of enol acetates [2] and [3], separated by GLC Treatment of [2] with boron trifluoride in methylene chloride at room temperature for 10 minutes gave (+) Camphor [U]. This synthesis is particularly interesting in that it is a chemical analogy for the biosynthesis conversion of a monocyclic into a bi-cyclic monoterpenoid. 

Indanyl)-phenol 16 was obtained by reacting p-methoxy-phenyl-acetic acid ethyl ester with benzylchloride to form a-benzyl-p-methoxyphenyl ethyl acetate, saponification into the acid, conversion of the acid with thionylchloride into the chloride, cyclization to 2-p-methoxy-phenyl-l-indanone, NaBH4 reduction to 2-p-methoxyphenyl-l-indanole, dehydration with p-toluene-sulphonic acid in toluene to 2-p-methoxyphenyl-indene, catalytic hydrogenation to 2-p-methoxyphenyl-indene, and treating the ether with HBr [Eq. (5)]. 

The absence of a distinct maximum for AC for the solvolysis of substituted benzyl chlorides in 70% acetone (see Table 8) could be a consequence of the fact that the difference between AC for S l and Sif2 reactions is generally greater for reaction in this solvent than in 50% acetone. However, the similar observation for the solvolysis of the benzyl -toluene-sulphonates (Table 9) cannot be explained in this manner since all the available evidence suggests that a change of mechanism only has a very small effect on AC for these reactions. 

It must be assumed that higher [l,m,n]-eliminations (m n, m > 2, n S 2) can be found and developed in a large variety of ways. The synthetic potential of those types can be indicated with some examples Thus, the thermal conversion of 202 to 204 (48%)113) can be reasonably formulated via initial [l,3,4]-elimination of hydrogen chloride to produce the intermediate bicyclobutane 203 which is stabilized by a [1,2/2, -rearrangement. The base-induced reaction of 205 (55%) leads to the displacement of p-toluene-sulphonic acid and to the migration of the inner chain bond 114). Therefore, it must be classified as [l,3,(2)4]-elimination. The dehydroxy-silylation of 207 to 208 (20%)115) is typical for [l,4,(3)2]-eliminations (migration of the Se—C-chain bond). 

The hot solution from step 5 is then filtered under gravity, to remove any undissolved sodium chloride, and cooled in ice. The white crystals of the deuterated sodium p-toluene sulphonate sodium salt are collected by filtration using a Buchnerfunnel and the product is recrystallized from hot water and dried in a vacuum oven at 100°C... 

Poly(2-alkyl oxazoline)s having methacrylate or acrylate end groups were prepared by two methods [182]. a) Living polyoxazoline chains, prepared using methyl p-toluene sulphonate as initiator, were end-capped by reaction with metal salts or tetraalkylammonium salts of acrylic or methacrylic acid or a trialky-lammonium salt or trimethylsilyl ester of methacrylic acid (functional termination). b) The living polymers were terminated with water in the presence of Na2C03 to provide hydroxyl-terminated chains. Subsequent acylation with acry-loyl or methacryloyl chloride in the presence of triethylamine led to the formation of the macromonomers. The procedures are outlined in the following Scheme 51. 

For the synthesis of (2/ ,2 / )-oscillol (II), the aglycone of oscillaxanthin (208), the AD was selected [1IJ. The starting material 3-methylbut-2-enol (12) was converted, with p-nitrobenzoyl chloride, into the ester 13 (yield 88%). After AD the diol 14 was converted, with p-toluene-sulphonic acid, into the acetal 15 and seven further steps gave the Cio-phosphonium salt 16 which, in a Wittig reaction with crocetindialdehyde (77) gave (2/ ,2 / )-oscillol (//) (Scheme 6). 

Normally the reaction of thiols with carbonyls, saturated or unsaturated, leads to the formation of dithioacetals when acid catalysts such as zinc chloride or p-toluene-sulphonic acid are present (see section II.A. 1). Occasionally, under special reaction conditions thioenol ethers have been formed using these same catalysts but never in the presence of acid-sensitive substituents. Pyridine hydrochloride as the catalyst has been successfully used to give excellent yields of the thioenol ethers of A -3-ketosteroids even in the presence of sensitive groups . Thus, desoxy-corticosterone acetate (92) was converted to its 3-benzylthioenol ether... 

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