Mesitylene, sulfonation

Compounds i, ii, and iii can be prepared by an acid-catalyzed reaction of a diol and the cycloalkanone in the presence of ethyl orthoformate and mesitylene-sulfonic acid. The relative ease of acid-catalyzed hydrolysis [0.53 M H2SO4, H2O, PrOH (65 35), 20°] for compounds i, iii, acetonide, and ii is C5 C7 > acetonide C (e.g., t.//s for 1,2-O-alkylidene-a-D-glucopyranoses of C5, C7, acetonide, and C derivatives are 8, 10, 20, and 124 h, respectively). The efficiency of cleavage seems to be dependent upon the electronic environment about the ketal. ... 

The combined distillates are treated with an equal volume of concentrated sulfuric acid and the solution wanned on a water bath for an hour, under a reflux condenser, with occasional shaking or, better, with mechanical stirring. Upon cooling, mesitylene sulfonic acid crystallizes and the unsulfonated material remains as an oil on the surface. The mixture is filtered through flannel or a filtrose plate, and the crystals are washed with 60-70 per cent sulfuric acid. The oily layer is again warmed with sulfuric acid, as before. The acid and oily filtrates from the two sulfuric acid treatments are steam distilled, and the distillate combined with the next batch of material. The crystals are mixed with 2 1. of 15.per cent hydrochloric acid and heated under a reflux condenser for two to three hours. The reaction mixture is now steam distilled, the mesitylene separated, dried over calcium chloride and fractionated the portion which boils at 163-167° is collected. 

The parent system 175 was prepared in 90% yield by cyclization of 3-amino-2-formamido thiazolium mesitylene sulfonate, which, in turn, was readily obtained by reaction of 2-formamido-thiazole with O-mesitylensul-fonylhydroxylamines (colorless crystals with mp 98-100°C). The hydrochloride was prepared by passing dry hydrogen chloride into an etheral solution of 175 (mp 226-227°C) (74JHC459). 

A series of eleven 1-aminopurinium mesitylene sulfonates were prepared in good yields by treatment of the corresponding purine with O-(mesitylenesulfonyl) hydroxylamine <85RTC302>. 

NMR spectra of 24 (mesitylene-sulfonate salt) in the presence of increasing amounts off ion molar ratio f/24 = Q a = 0 b = 0.25 c = 0.5 d = 2.0, internal standard tert.butanol b Plot of the changes in chemical shift versus molar ratio Q = N—CHj protons ... 

Phenylcinnoline (19) gave l-amino-3-phenylcinnoUn-l-ium mesitylene-sulfonate (19a) [substrate, CH2CI2, 2,4,6-Me3C6H2S(=0)20NH2 in CH2Cl2i dropwise, 0°C then 20°C, 10 min 65%). ... 

Nitrations can be performed in homogeneous media, using tetramethylene sulfone or nitromethane (nitroethane) as solvent. A large variety of aromatic compounds have been nitrated with nitronium salts in excellent yields in nonaqueous media. Sensitive compounds, otherwise easily hydroly2ed or oxidized by nitric acid, can be nitrated without secondary effects. Nitration of aromatic compounds is considered an irreversible reaction. However, the reversibihty of the reaction has been demonstrated in some cases, eg, 9-nitroanthracene, as well as pentamethylnitrobenzene transnitrate benzene, toluene, and mesitylene in the presence of superacids (158) (see Nitration). 

By the methylation of commercial xylene and separation of the mesitylene from the mixture of hydrocarbons by crystallization of the sulfonate. Smith and Cass, J. Am. Chem. Soc. 54, 1603 (1932). 

N 16.47%, OB to C02 —103.4%, triclinic needles (from ale). prisms (from acet), mp 238.2°, bp expl at 415°, d 1.48g/cc. Insol in w, si sol in hot ale eth, misc in hot acet benz. Can be prepd by treating mesitylene with a mixt of. nitric sulfuric acids in the cold (Refs 2 3). Blanksma (Ref 4) prepd it by dissolving mesitylene in sulfuric acid, partial sulfonation taking place, and then adding the soln to nitric acid, with the pptn of trinitio-mesitylene. Kholevo (Ref 6) nitrated mesitylene with nitric acid 27, sulfuric acid 69, water 4% to yield white crysts. The expl power of trinitro-mesitylene is less than PA (Ref 9), and it develops a bomb press 84% that of TNT (Ref 8), Its impact sensitivity is 52% that of TNT (Ref 7), and it expls at 415° (Ref 5)... 

Stabilization and crystallization of [Cr f/x-OI 0/0112)J(3j y>+ cations have been achieved by exploiting the supramolecular interactions with large anionic assemblies initially with mesitylene-2-sulfonate or its adduct with 18-crown-6,837-839 and subsequently with the adducts of calixarene sulfonates with N- or O-macrocycles.840,841 This approach, illustrated in Scheme 27, allowed the crystal structures of di-, tri- and tetrameric Cr111 complexes, (165)-(167),837,839-841 as well as that of a heteropolynuclear complex, [(H20)4Rh(/i-0H)2Cr(0H2)4]4+,838 to be determined. 

Fig. 5b. General synthetic scheme of mesitylene type enterobactin analogs. TRIMCAMS and (NaAc)-MECAMS are obtained by sulfonation of TRIMCAM and MECAM...

Decyl-phenyl- und -(2,4,6-trimethyl-phenyl)-sulfon werden durch Lithium/Methyl-amin zu Decansulfinsaure (95 bzw. 80% d.Th.) und Benzol bzw. Mesitylen (55% d.Th.) reduziert1. Methyl-phenyl-sulfon und Benzyl-phenyl-sulfon ergeben mit Natriumamal-gam in siedendem Athanol Benzolsulfinsaure2. 

Aromatic hydrocarbons such as toluene, xylenes, mesitylene, and methyl-naphthalenes can be sulfonated in dichloroethane almost quantitatively by the dioxan-sulfur trioxide complex under very mild conditions (2 h at 20°).179... 

Protection of Phosphates and Phosphonates. 2-Hydroxy ethyl phenyl sulfone (1) has been used to differentially protect phosphate esters for nucleotide synthesis. Thus, reaction of the diphosphate (8) with 1 and l-(mesitylene-2-sulfonyl)-3-nitro 1,2,4-trIazole (MSNT) in pyridine afforded the differentially protected phosphate 9 in very good yield (eq 5). The 2-phenylsulfonylethyl phosphate can be cleaved under mild conditions by treatment with triethylamine. 

Fig. 21.13 The structure of [Cr2(OH2)g( J,-OH)2] determined by X-ray diffraction for the mesitylene-2-sulfonate salt the non-bonded Cr—Cr separation is 301 pm [L- Spiccia et al. (1987) Inorg. Chem., vol. 26, p. 474]. Colour code Cr, green ...

Toluene sulfonates more readily than benzene, while o- and n-xylcnc and mesitylene may be slowly sulfonated with 95 per cent II2SO4, even without heating. Para derivatives, such as p-xylcnc, dissolve less readily (separation of the xylenes), while p-dihalogcn benzenes require 20 per cent fuming sulfuric acid and heating to 100° to 120° for sulfonation. Substitution in naphthalene takes place more readily than in benzene and therefore concentrated H2SO4 may be used. 

Formylation of aromatic compounds such as benzene, toluene, xylenes, mesitylene, indan, tetralin, fluoro- chloro- and bromobenzene in HSOsF-SbFs under atmospheric CO pressure at 0°C was achieved in high yields (SubstrateiHSOsFiSbFs mol ratio of 20 174 138). Linder reduced molar ratios of SbFs HS03F both formylation and sulfonation take place. 

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