A/chlorosuccinimide-dimethyl sulfide

Related Reagents. A/-Chlorosuccinimide-Dimethyl Sulfide Chromic Acid Dimethyl Sulfide-Chlorine Dimethyl Sulfoxide-Acetic Anhydride Dimethyl Sulfoxide-Dicyclo-hexylcarbodiimide Dimethyl Sulfoxide-Oxalyl Chloride Dimethyl Sulfoxide-Phosphorus Pentoxide Dimethyl Sulfoxide-Sulfur Trioxide/Pyridine Dimethyl Sulfoxide-Trifluoroacetic Anhydride Dimethyl Sulfoxide-Triphosgene Manganese Dioxide Pyridinium Chlorochromate Pyridinium Dichromate Ruthenium(rV) Oxide Silver(I) Carbonate on Celite 1,1,1-Triacetoxy-1,1-dihydro-1,2-benziodoxol-3( 1 H)-ons. 

Related Reagents. Acetyl Chloride Bromotrimethylsi-lane A-Chlorosuccinimide-Dimethyl Sulfide Dichloroborane Diethyl Etherate Hydrogen Chloride Iodine lodotrimethyl-... 

Selective conversiou of allylic and benzylic alcohols into halides It was noted above that allylic or benzylic alcohols are not oxidized by the N-chlorosuccinimide-dimethyl sulfide reagent but instead are converted into chlorides. Corey et al. now report that this procedure can be used to form allylic and benzylic chlorides in high yield if the sulfoxonium intermediate corresponding to (3, above) is allowed to decompose in methylene chloride without addition of a tertiary amine. For example, the allylic or benzylic alcohol is treated with the complex of N-chlorosuccinimide-dimethyl sulfide as above in methylene chloride and then allowed to stand for 4 hr. at - 25°. In the case of benzhydroi [(CfcH5)2CHOH], benzhydryl chloride can be obtained in > 95% yield. 

Olefinic aldehydes have been synthesized by a variety of methods including oxidation of the corresponding primary alcohols with the chromium trioxide-pyridine complex 195—197) or N-chlorosuccinimide-dimethyl sulfide complex 198), heating a primary alken-l-yl mesylate with dimethylsulfoxide 199), or by alkylation of the lithium salt of 5,6-dihydro-2,4,4,6-tetramethyl-l,3-(4H)-oxazine with an alkynyl iodide followed by sodium borohydride reduction and acid hydrolysis (200). 

Many of the reactions of A-chloro- and A-bromo-imides are extremely violent or explosive. Those observed include A-chlorosuccinimide with aliphatic alcohols or benzylamine or hydrazine hydrate A-bromosuccimmidc with aniline, diallyl sulfide, or hydrazine hydrate or 3-nitro-A-bromophthalimide with tetrahydrofur-furyl alcohol l,3-dichloro-5,5-dimethyl-2,4-imidazolidindione with xylene (violent explosion). Individually indexed compounds are ... 

Treatment of various 2-aminopyridines and of 1-aminoisoquinoline with dimethyl sulfide and N-chlorosuccinimide gives the corresponding salt which on deprotonation with base provides a sulfilimine (e.g. 98) (76JCS(P1)2166>. Oxidation of the latter with m-chloroperben-zoic acid gives the corresponding nitroso heterocycle (Scheme 85). 

Although the Corey-Kim oxidation is not used as often as the Swern oxidation—probably because of the bad odour of dimethyl sulfide—it offers the advantage of allowing an operation above -25°C. Typically, NCS (A-chlorosuccinimide) and Me2S are mixed in toluene at 0°C, resulting in the formation of a precipitate of activated DMSO. The reaction mixture is cooled to ca. —25°C and the alcohol is added for activation. This is followed by addition of Et3N and allowing the reaction to reach room temperature. 

OxUatiou of primary and secondary alcohals to carbonyl compounds. Corey and Kim report that the complex of N-chlorosuccinimide and dimethyl sulfide is somewhat superior to the complex of dimethyl sulfide and chlorine (this volume) for oxidation of primary and secondary alcohols the formation of hydrogen chloride is avoided and yields are generally higher. The procedure is illustrated for the oxidation of 4-r-butyl-cyclohexanol (2) to 4-r-butylcyclohexanonc (4). The complex (1) is prepared by addition of dimethyl sulfide (4.1 mmole) to a stirred solution of NCS (3.0 mmole) in toluene at 0° under argon. The mixture is cooled to -25° and a solution of 4-r-butylcyclo-hexanol (2.0 mmole, mixture of cis and trans) in toluene is added dropwise. The stirring is continued for 2 hr. at — 25° and then triethylamine (3.0 mmole) in toluene is added dropwise. The ketone (4) is obtained in almost quantitative yield. As in oxidation with the complex of dimethyl sulfide and chlorine, an intermediate sulfoxonium complex (3) is involved. 

A -Chlorosuccinimide, C4H4CINO2 (mp 144-146 C), either alone [709] or in the presence of dimethyl sulfide [720, 721], dehydrogenates alcohols to carbonyl compounds. 

Dimethyl sulfide and chlorine or, better still, dimethyl sulfide and N-chlorosuccinimide, form a system capable of the selective dehydrogenation of alcohols to aldehydes or ketones. The intermediates, such as (013)28 C1 Cr, react with bases according to the scheme in equation 25 [720],... 

Dimethyl sulfide and chlorine or A-chlorosuccinimide (NCS) oxidize primary alcohols to aldehydes in high yields under very mild conditions. 

A mixture of N-chlorosuccinimide and dimethyl sulfide oxidizes alcohols to ketones under very mild conditions and in high yields. The treatment of 4-tm-butylcyclohexanol with this mixture in toluene at 0-25 °C, followed by the addition of triethylamine in toluene, results in a 90-93% yield of 4-tert-butylcyclohexanone [721]. 

To a stirred solution of 0.400 g (3.0 mmol) of A -chlorosuccinimide in 10 mL of analytical-grade toluene is added, at 0 °C, 0.3 mL (4.1 mmol) of dimethyl sulfide under argon. A white precipitate is formed immediately after the addition. The mixture is cooled to -25 °C with carbon tetrachloride-dry ice. A solution of 0.312 g (2.0 mmol) of 4-rerr-butylcydohexanol (a mixture of cis and trans isomers) in 2 mL of toluene is added dropwise while the mixture is stirred for 2 h at -25 °C. Then a solution of 0.303 g (3.0 mmol) of triethylamine in 0.5 mL of toluene is dropped in, the cooling bath is removed, and after 5 min, 20 mL of ether is added. The organic layer is washed with 5 mL of water, dried with anhydrous magnesium sulfate, and evaporated to give 0.310 g ( 100%) of 4-rcrr-butylcydo-hexanone as white plates, mp 44-47 C. 

Dimethyl(succinimido)sulfonium fluorosulfate 2, easily prepared from A -chlorosuccinimide (1), dimethyl sulfide, and methyl fluorosulfate, reacted with 1-dialkylaminocycloalkenes 3 to give fair yields of (2-dialkylaminocycloalk-l-enyl)dimethylsulfonium fluorosulfates 4 or their thermally rearranged allylic isomers At elevated temperatures 4 or 5, respectively, reacted... 

The alcohol (1.5 L, 208 g, 280 mmol) in THF is charged to a jacketed flask followed by dimethyl sulfide (37 g, 590 mmol) and diisopropylethylamine (47 g, 364 mmol). The solution is cooled to approximately -13 °C. 7V-Chlorosuccinimide (NCC 71 g, 532 mmol) is dissolved in THF (240 mL) and added to the flask at a rate so as to maintain the internal temperature at -11 to -13 °C. The mixture is then stirred at -15 5 °C for 3 h. Isopropyl acetate (3 L) is added followed by 0.5 N NaOH (1.2 L). The mixture is warmed to room temperature and stirred for 1 h. The organic layer is washed with 5% NaCl (2 x 600 mL) and brine (2 x 600 mL). The product layer is concentrated under vacuum to obtain, at first, a yellow amorphous solid which when dried under high vacuum turns into a white foam. Slurrying the solid in warm water followed by filtration and drying afforded 196 g (94%) of the 3-ketomacrolide as a white solid after trituration with 10% EtOAc/heptane. 

The starting material, l,3-dibenzyloxy-2-propanol 265, is easily oxidized to the ketone 408 using N-chlorosuccinimide and dimethyl sulfide. Compound 408 was smoothly converted into the epoxide 409. The epoxide ring was opened by the attack of benzylate anion at the least hindered site to produce 2-benzyloxymethyl-l,3-dibenzyloxy-2-propanol (410), which was activated as the thiomethyl ether system 411 using acetic anhydride in DMSO. The thiomethyl ether is readily activated by iodine, allowing nucleophilic attack at the methylene position. As a result, compound 411 was... 

An alternative method for the formation of aldehydes or ketones makes use of the complexes formed from a methyl sulfide with chlorine or A-chlorosuccinimide (NCS), in what is called the Corey-Kim oxidation. With dimethyl sulfide the salt 28 is generated and reacts with the alcohol to give the alkoxysulfonium salts and hence, on treatment with a base, the carbonyl compound. This reaction has fovmd particular application in the oxidation of 1,2-diols in which one alcohol is tertiary, to give a-hydroxy-aldehydes or ketones without rupture of the carbon-carbon bond. For example, the aldehyde 32 is formed in good yield from the diol 31 using dimethyl sulfide and NCS followed by addition of triethylamine (6.29). This transformation is thought to depend on the preferential five-membered transition... 

To a solution of Ai-chlorosuccinimide (133 mg, 1.0 mmol) in CH2CI2 was added 75 mg dimethyl sulfide (1.2 mmol) at -78°C, and the mixture was stirred for 1 h. To this reaction mixture, was added a solution of 109 mg indole derivative (0.5 mmol) in CH2CI2 and 155 mg diisipropylethylamine (1.2 mmol) the whole mixture was stirred for 2 h at -78°C. The mixture was treated with cooled brine and extracted with CH2CI2. The combined organic layers were washed and dried over MgS04. After evaporation of the solvent,... 

Oxidation of alcohols under extremely mild conditions can be effected using a procedure that is mechanistically related to the DMSO method. Dimethyl sulfide is converted to a sulfonium derivative by reaction with N-chlorosuccinimide. This sulfur species reacts readily with alcohols, generating the same kind of alkoxysul-fonium salts that are involved in the DMSO procedures. In the presence of mild base, elimination of dimethyl sulfide completes the oxidation. ... 

A mixture of 1-morpholinocyclohexene, N-chlorosuccinimide, and dimethyl sulfide in methylene chloride stirred 2 days at room temp. 2-morpholino-3-chloro-cyclohexene. Y 77%. F. e. s. E. Vilsmaier, W. Spriigel, and K. Gagel, Tetrah. Let. 1974, 2475. 

Dimethyl sulfide allowed to react with f rf-octylamine in methylene chloride in the presence of 1-chlorobenzotriazole crude N-r rr-octyl-S,S-dimethylimino-sulfonium chloride. Y 90%. F. e., also with N-chlorosuccinimide, and related reactions s. A. D. Dawson and D. Swern, J. Org. Chem. 42, 592 (1977). 

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