Mesitylenesulfonyl chloride

Alternate Name 2,4,6-trimethylbenzenesulfonyl chloride. Physical Data mp 55-57 °C. 

Form Supplied in white crystalline solid widely available. Purification can be recrystallized from hexane or pentane. Handling, Storage, and Precautions corrosive moisture sensitive handle and store under nitrogen. 

Sulfonamide Formation. Reaction of mesitylenesulfonyl chloride with amines in the presence of Pyridine or Triethylamine yields the corresponding sulfonamides (eq 1 ), which have been used as intermediates in synthesis. 

The mesityl group has been used as a protecting group for various amines including amino acids (eq if and peptides.  

Sulfonate Formation. Treatment of alcohols with mesitylenesulfonyl chloride yields the corresponding sulfonates. Mesitylenesulfonyl chloride is particularly useful for the selective sulfonation of polyhydroxylic systems such as carbohydrates (eq 4). It is more selective than p-Toluenesulfonyl Chloride, which has been frequently used but gives mixtures of products. Unfortunately, the mesitylenesulfonates are not as reactive as the corresponding to-sylates. Numerous 1 -derivatives of sucrose have been synthesized via mesitylenesulfonyl derivatives.  

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Mesitylenesulfonyl chloride 2-Mesitylenesulfonyl chloride (8) Benzenesulfonyl chloride, 2,4,6-trimethyl- (9) (773-64-8)... 

This reaction was used to introduce the final two skeletal carbons in a total synthesis of maytansine (4).2 The reaction of the 2,/ -unsaturated aldehyde (2) with I (R = C6H5) gives the desired 4,5-unsaturated 3-hydroxy ester 3 in 80% yield. The ratio of the desired (S)-alcohol to the epimer is 93 7. The resulting amino acid was cyclized to the lactam in 80% yield with mesitylenesulfonyl chloride (8, 318-319). Epoxidation by the Sharpless procedure (9, 78 79) was also highly stereoselective, giving the desired epoxide and the undesired epimer in the ratio > 200 1. 

Sulfonylation of free sucrose with 3 equiv. of p-toluenesulfonyl chloride in pyridine affords the l, 6,6 -tri-tritosylated sucrose in moderate yield,151,152 accompanied by the 6,6 -di-substituted as well as penta- and tetra-substituted derivatives. Using the more bulky mesitylenesulfonyl chloride, the T,6,6 -tri-sulfonylated derivative was obtained in 55% yield.152 Direct regioselective 2-p-toluenesulfonylation of sucrose with 7V-(/>-toluenesulfonyl)imidazole has been reported.106... 

Using the equipment in Figure 1, but without the HCI gas trap attached, mesitylenesulfonyl chloride (109.7 g, 0.503 mmol, Note 7) is dissolved in 175 mL of dry tetrahydrofuran (THF) and cooled to between -10°C and 0°C in a wet ice-acetone bath. Hydrazine monohydrate (63.0 g, 61.0 mL, 1.26 mol) (Note 3) is dissolved in 30 mL of ice-cold water and added so that the temperature remains below 25°C (Note 10). After the addition is completed, the mixture is stirred for an additional 45 min at room temperature and poured into 250 mL of ice water with stirring. Crude mesitylenesulfonylhydrazine is recovered by suction filtration and then dissolved in 500 mL of dichloromethane. A 150- to 175-mL portion of water separates. The water layer is removed, and the organic layer is washed with one 50-mL portion of ice-cold water, dried over sodium sulfate, filtered, and the solvent is removed on a rotary evaporator. The crystals are triturated in 250 mL of cold hexane, and the fluffy white product (95.4 g, 89%, Note 11) is recovered by suction filtration (Notes 12 and 13). 

Briefly warming the reaction mixture solubilizes all the mesitylenesulfonic acid and drives the reaction to completion. Mesitylenesulfonic acid is less soluble than mesitylenesulfonyl chloride. Therefore, after everything dissolves, conversion of the acid to the acid chloride is complete. The product is partially hydrolyzed if it is poured into water while it is still hot. 

Temperature control and efficient stirring are more important here than in the preparation of mesitylenesulfonyl chloride. Better yields are obtained when the temperature is kept below 25°C. Gas evolution accompanied by some decomposition occurs at elevated temperatures. 

Baker and Castro [69 e] reported that DCC, DPP A, or DPEC did not induce the macrocyclic lactam closure in the synthesis of the antitumor antibiotic ( + )-macbecin I, but it was achieved by mesitylenesulfonyl chloride. 

Protected derivatives of uridine and protected guanosine are activated by treatment with 2-mesitylenesulfonyl chloride, a tertiary base, and DMAP as the catalyst to the corresponding 4-0- or 6-0-mesitylenesul-fonyl derivatives, which react readily with hydroxypyridines or 0-nitrophenol to form the stable, reactive 143, as well as the 0-deprotected 144. These are readily aminated, especially after quaternization of the pyridyloxy moiety with methyliodide, by ammonia, methylamine, dimeth-... 

C9H10O3 alpha-(hydroxymethyl)benezeneacetic acid 529-64-6 32.41 1.1490 2 16866 C9H11Ci02S 2-mesitylenesulfonyl chloride 773-64-8 25.00 1.2387 2... 

Nucleotides. In an extensive investigation of various reagents for the formation of the 3, 5 -intemucleotide linkage, Jacob and Khorana concluded that the combination of DCC with p-toluenesulfonyl chloride or mesitylenesulfonyl chloride is the most efBcient. 

Mahadevan employs an insoluble copolymer of styrene (88%) -vinylbenzoic acid (12%) and -divinylbenzene (0.2% or 0.02 %>). The carboxyl groups on the polymer were converted into acid chlorides with thionyl chloride and allowed to react with 5 -O-trityl-2 -deoxycytidine (VIII) to yield IX. Condensation of IX with cyanoethylphosphate and mesitylenesulfonyl chlorixfe or DCC gave X. When X was activated with mesitylenesulfonyl chloride and... 

The rate of oligonucleotide synthesis by the triester method using mesitylenesulfonyl chloride was increased 5- to 10-fold when this group was used as a protective group during internucleotide bond formation. It was removed with coned. NH4OH at 60°C for 12 h or by the oximate method. ... 

Nucleotides [1, 235, lines 2-4], Correction. Change to read ..., Jacob and Khorana27 concluded that DCC, p-toluenesulfonyl chloride, or mesitylenesulfonyl chloride are the most efficient. Any one of these compounds is thus effective.273... 

With a bountiful supply of 69 at our disposal, the synthesis was continued by PCC oxidation to the aldehyde level and application of the Corey-Fuchs procedure [35] for chain homologation via dibromo olefin 70 to the acetylenic ester 71. Since amide bond construction next had to be implemented, this ester was saponified under mild conditions and the resulting carboxylic acid was activated by formation of a mixed anhydride with mesitylenesulfonyl chloride in advance of in situ condensation with 59. In order to preclude hydrolysis of the silyl ether functionality in 72, deacetalization had to be performed under anhydrous conditions in dry acetone containing a catalytic quantity of p-toluene-... 

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