Acetyl methanesulfonate

Acetyl methanesulfonate [5539-53-7] M 170.2, b <120 /<0.01mm. The main impurity is methanesulfonic acid. Reflux with redistd acetyl chloride for 6-lOh, i.e. until no further HCl is absorbed in a trap, and exclude moisture. Dist off excess of AcCl and carefully dist below 0.001mm with the bath temp below 120 to give the anhydride as a pale yellow oil which solidifies below 0 . Below -130 it decomp to the... 

A substrate with the C-C double bond of the 6-alkenyl substituent situated one carbon atom further out from the bicyclohexanone ring system was also examined. The best Lewis acid catalyst was found to be acetyl methanesulfonate which led to the formation of cedrone (17) and epicedrone (18). ... 

Preparation.1 The reagent is prepared in essentially quantitative yield from acetyl methanesulfonate and dimethoxymethane ... 

Acetyl methanesulfonate, A-00020 9-Anthracenecarbonyl chloride, in A-00378 (Azidocarbonyl)ferrocene, A-00459 (3-Azido-3-oxopropyl)ferrocene, A-00461 Azobenzene-4-carboxylic acid Chloride, in A-00467... 

Nearly all commercial acetylations are realized using acid catalysts. Catalytic acetylation of alcohols can be carried out using mineral acids, eg, perchloric acid [7601-90-3], phosphoric acid [7664-38-2], sulfuric acid [7664-93-9], benzenesulfonic acid [98-11-3], or methanesulfonic acid [75-75-2], as the catalyst. Certain acid-reacting ion-exchange resins may also be used, but these tend to decompose in hot acetic acid. Mordenite [12445-20-4], a decationized Y-zeohte, is a useful acetylation catalyst (28) and aluminum chloride [7446-70-0], catalyzes / -butanol [71-36-3] acetylation (29). 

Zinc chloride is a Lewis acid catalyst that promotes cellulose esterification. However, because of the large quantities required, this type of catalyst would be uneconomical for commercial use. Other compounds such as titanium alkoxides, eg, tetrabutoxytitanium (80), sulfate salts containing cadmium, aluminum, and ammonium ions (81), sulfamic acid, and ammonium sulfate (82) have been reported as catalysts for cellulose acetate production. In general, they require reaction temperatures above 50°C for complete esterification. Relatively small amounts (<0.5%) of sulfuric acid combined with phosphoric acid (83), sulfonic acids, eg, methanesulfonic, or alkyl phosphites (84) have been reported as good acetylation catalysts, especially at reaction temperatures above 90°C. 

Subsequently this route to 3-deoxy sugars was developed by further work in our laboratory by Ferrier and Sankey (23). They demonstrated that although tetra-O-acetyl-2-hydroxy-D-galactal undergoes rearrangement in boiling acetic acid, and that reaction is speeded up and goes to completion if catalytic amounts of methanesulfonic acid are added, the... 

Treatment of 51 with an excess of sodium benzoate in DMF resulted in substitution and elimination, to yield the cyclohexene derivative (228, 36%). The yield was low, but 228 was later shown to be a useful compound for synthesis of carba-oligosaccharides. <9-Deacylation of228 and successive benzylidenation and acetylation gave the alkene 229, which was oxidized with a peroxy acid to give a single epoxide (230) in 60% yield. Treatment of 230 with sodium azide and ammonium chloride in aqueous 2-methoxyeth-anol gave the azide (231,55%) as the major product this was converted into a hydroxyvalidamine derivative in the usual manner. On the other hand, an elimination reaction of the methanesulfonate of 231 with DBU in toluene gave the protected precursor (232, 87%) of 203. 

The 4-0- (282) and 4,7-di-O-methanesulfonates (283) of a-DL-carba-galactopyranose obtained from 258 produced, after azidolysis in DMF, hydrogenolysis, and acetylation, penta-A, 0-acetyl-4-amino- (284) and 4,7-diamino-4,7-dideoxy-o -DL-carba-glucopyranose (285). 

Compound 102 is used as the building block for the syntheses of PNU-86093 and its analogues, as described in Scheme 21. Namely, the Friedel-Crafts acetylation reaction of 102 under acetic anhydride, methanesulfonic acid, and methanesulfonyl anhydride [51,65] affords compound 103 (PNU-... 

The 4-amino group of 31 was selectively acetylated under acidic conditions using acetic anhydride (1 equiv.) and methanesulfonic acid (1 equiv.) in acetic acid and f-butylmethyl ether to give 32. Deallylation of 32 using 10% Pd/C in the presence of ethanolamine in refluxing ethanol proceeded as before to afford 1, which was converted to the phosphate salt in 70% yield with high purity (99.7%). The overall yield of 1 from epoxide 23 was 35-38%. 

Corey and Ishihara s synthesis of phe-box ligand 29 began with the trifluoro-acetyl derivative of (5)-phenylglycine 26. Treatment of 26 with methylmagnesium iodide, as shown in Figure 9.7, followed by potassium hydroxide in methanol afforded amino alcohol 27 in 88% yield (2 steps).This was then acylated with dimethylmalonyl dichloride 24 and triethylamine followed by cyclization using methanesulfonic acid at reflux to afford phe-box ligand 29 in 78% yield. 

F,SCH, Methanesulfonic acid, trifluoro-iridium, manganese and rhenium complexes, 26 114, 115, 120 platinum complex, 26 126 OiFeCgH, Iron, acetyl dicarbonyl (if -cyclopentadienyl)-, 26 239 0,FeN2C2 Hll(, Iron, tricarbonylbis(2-isocy-ano-l,3-dimethylbenzene)-, 26 54 0.iMoNaCHH5-2 C4H ,02, Molybdate 1 -), tricarbonyl(T) -cyclopentadienyl)-sodium, compd. with 1,2-dimethoxy-ethane-(l 2), 26 343 0,NaWC H5-2 C4H ,02, Tungstate(l -), tricarbonyl(ris-cyclopentadienyl)-... 

This reaction has been used to trap oxepin oxides (78TL2995). Extrusion of nitrogen from the azodiepoxide (157) in the presence of methanesulfonic acid gives 4-acetyl-4-methylpyran (160) as the only observable product. However, in the absence of acid, the aldehyde (161) is formed. This observation is attributed to an equilibrium between the two epoxides (158) and (159) which is in favour of the latter. 

The condensation of 2-nitrobenzenesulfonyl chlorides with 3-amino-2-chloropyridine in the presence of pyridine at 60 °C gave the corresponding sulfonamides, which were reacted with sodium hydride and iodomethane to give the N-methylated products. Catalytic hydrogenation of the N-methylated compounds followed by acetylation, treatment with sodium hydride in DMF, and reaction with arylalkyl chlorides or methanesulfonates resulted in the formation of novel benzo[/]pyrido[]3,2-r-][l,2,5]thiadiazepines <2005JME7363>. 

Acetyl-4,6-dimethoxyphenyl)-l, 2-hydrazinedicarboxylic acid bis(2,2,2-trichloroethyl) ester 1,2-Hydrazinedicarboxyiic acid, l-(2-acetyl-4,6-dimethoxyphenyl)-, bis(2,2,2-lrichloroethy ) ester (13) (154876-13-8) Trifluoromethanesulfonic acid Methanesulfonic acid, trifluoro- (8,9) (1493-13-6) Bis(2,2,2-trichloroethyl) azodicarboxylate Diazenedicarboxylic acid, bis(2,2,2-trichloroethyl) ester (9) (38857-88-4)... 

ACIDS, ORGANIC Acetyl sulfuric acid. d-(+)-Camphor-10-sulfonic acid. Formic acid. Methanesulfonic acid. Picric acid. p-Tolucnesulfonic acid. Trichloroacetic acid. Trifluoroacetic acid. Trifluorometh-ancsulfonic acid. 

MERCAPTANS l-Acetyl-2-thiouiea. METHANESULFONATE ESTERS Meth-anesulfonyl chloride. 

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