Methanesulfinyl chloride

A mixture of 0.10 mol of the acetylenic alcohol, 0.12 mol of triethylamine and 200 ml of dichloromethane (note 1) was cooled to -50°C. Methanesulfinyl chloride (0.12 mol) (for its preparation from CH3SSCH3, (08300)30 and chlorine, see Ref. 73) was added in 10 min at -40 to -50°0. A white precipitate was formed immediately. After the addition the cooling bath was removed and the temperature was allowed to rise to -20°0, then the mixture was vigorously shaken or stirred with 100 ml of water. The lower layer was separated off and the aqueous layer was extracted twice with 10-ml portions of CH2CI2. The combined solutions were dried over magnesium sulfate and concentrated in a water-pump vacuum (note 2). The yields of the products, which are pure enough (usually 96%) for further conversions, are normally almost quantitative. 

Pure methanesulfinyl chloride boils at 48° (22 mm.) and 59° (42 mm.) and has 1.5038, d° 1.4044 and df 1.3706. On standing at room temperature, it slowly decomposes with the liberation of hydrogen chloride. It should not be stored for a long period in a tightly sealed container. 

The utility of methanesulfinyl chloride lies in its great chemical reactivity. Through its ready hydrolysis, it serves as a convenient source of methanesulfinic acid. It reacts at low temperature with aromatic amines to form sulfinamides, and with alcohols to form sulfinate esters. When it is hydrolyzed in the presence of an equimolar quantity of sulfenyl chloride, a thiol-sulfonate ester is produced. 

Methyl-J-propynyl Sulfoxide from PropynyUithium and Methanesulfinyl Chloride... 

Methyl phenyl sulfoxide has also been prepared from thio-anisole by the action of hydrogen peroxide,2,3 lead tetraacetate,4 and dinitrogen tetroxide,5,6 and from methanesulfinyl chloride and benzene with anhydrous aluminum chloride.7... 

Homologation of a,fl-umatwrated carboxylic acids. Ethyl crotonate can be alkylated at C3 by CuCl-catalyzed addition of Grignard reagents followed by treatment with methanesulfinyl chloride. Subsequent desulfinylation yields the homologated unsaturated ester (equation I). The method is also applicable to a,/ -enones (equation II).10... 

Mercury(II) pivalate, 319 Mercury(II) trifluoroacetate, 320 Mesembranol, 169 a-Methallyl alcohol, 258 Methanesulfinyl chloride, 248 Methanesulfonic acid, 321 Methanesulfonyl chloride, 322 Methanol-sodium tetraborate, 322 Methoxyamine, 322-323 et Methoxy-a-arylacctic acid esters, 411 p-Methoxybenzyl ethers, 166, 167 Mcthoxycarbonylketene, 340, 341 4(R)-Methoxycarbonyl-l,3-thiazolidine-2-thione, 323-324... 

Methaneperoxoic acid, see Peroxyformic acid, 0419 Methanesulfinyl chloride, 0434 Methanesulfonic acid, 0486 Methanesulfonyl azide, 0464... 

Isophthaloyl chloride, 2883 f Isopropyl chloroformate, 1555 Methanesulfinyl chloride, 0434 Methoxyacetyl chloride, 1161 4-Methoxybenzoyl chloride, 2925 f Methyl chloroformate, 0732 Oleoyl chloride, 3766 Oxalyl dibromide, 0580 Oxalyl dichloride, 0602... 

Table 19. Influence of the Base and Solvent on the Stereochemistry of the Reaction of DAG with Methanesulfinyl Chloride...

Table 22. Reaction of Methanesulfinyl Chloride with Different Chiral Secondary...

Oxidations by chlorine are limited to only few types of compounds. In organic solvents and pyridine [681] or hexamethylphosphoramide (HMPA) [682] as cosolvents, primary alcohols are oxidized to aldehydes and secondary alcohols to ketones [681, 682]. Secondary alcohols are oxidized in preference to primary alcohols [681]. Many oxidations with chlorine are carried out in aqueous media and involve sulfur-containing compounds. Mercaptans [683], alkyl thiolcarboxylates [683], thiocyanates [684], isothioureas [684], disulfides [655], and sulfinic acids [656] are transformed into sulfonyl chlorides. The chlorination of dimethyl disulfide in acetic anhydride yields methanesulfinyl chloride [657]. 

Under anhydrous conditions, chlorine converts dimethyl disulfide into methanesulfinyl chloride by a sequence of reactions (equation 586) [687],... 

Sulfines derived from simple aldehydes and ketones are rather unstable and generally appear as transient species. Sulfine (36) has been generated by flash vacuum thermolysis of, for instance, 1,3-dithietan-l-oxide (37) or methanesulfinyl chloride (38) (Scheme 20). However, the dehydrochlorination of a sulfinyl chloride, like (39), by a tertiary amine is a common route to obtain a stable sulfine, like (40) (Scheme 21). 

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