Dichloromethyl sulfide

Elimination of hydrogen chloride from 1,1-dichloromethyl sulfide with potassium tcrt-butoxide affords chloromethylthiocarbene [J] (equation 5)... 

Sulfur substituted carbenes have been generated by the phase transfer method with reasonable success. Treatment of either phenyl(chloromethyl) sulfide or phenyl-(dichloromethyl) sulfide with 50% aqueous sodium hydroxide solution in the presence of both an olefin and a phase transfer catalyst (usually BTEAC) results in the... 

S mmetrical dichloromethyl sulfide is formed when tiithiofoimaldehyde is 1 eacted with sulfiii chloiides. When sulfur dichloridc is employed, symmetrical dichloromethyl sulfide is obtained in practically quantitative yield according to the following equation ... 

Several chlorophyll derivatives have been prepared by electrophilic substitution, inter alia by formylation reactions. Adopting methods from corrin chemistry.50 alkylation with chloro-methyl methyl ether (caution toxic),32k chloromethyl methyl sulfide,51 and dichloromethyl methyl ether (caution toxic)52 in the presence of Lewis acids are the methods of choice to introduce carbon residues into the chlorin frame work. The compounds listed below have been prepared by these methods. 

Alkyl- or aryl-dibenzothiophenes are conveniently prepared from the 2-arylthio-cyclohexanones, which are readily cyclized and dehydrogenated to yield the respective 1-, 2-, 3- or 4-substituted dibenzothiophenes (382 equation 9 Section 3.15.2.3.2). More complex polycyclic systems are available, using suitable aryenethiols, such as naph-thalenethiols, and 2-bromo-l-tetralone to synthesize the appropriate 2-arylthio ketones. Diaryl sulfides can be converted to dibenzothiophene derivatives in satisfactory yields by photolysis in the presence of iodine (equation 10) (75S532). Several alkyldibenzothiophenes with substituents in the 2- and/or 3-positions were prepared in satisfactory yield by the condensation of dichloromethyl methyl ether with substituted allylbenzo[6]thiophenes (equation 11) (74JCS(P1)1744). 

Aldehydes Dichloromethyl methyl ether. p-Dimethylaminobenzaldehyde. Dimethyl sulfide. Lithium tri-r-butoxyaluminum hydride. Nickel catalysts, Raney type. Sodium nitrite-CFjCOjH-DMSO. Titanium tetrachloride. Triethyl orthoformate. Trimethylamine oxide. u-Alkoxy ketones BFa-etherate. 

Thus dichloromethyl methyl sulfone (2.02 g, 84 %) is formed when dichloromethyl methyl sulfide (1.93 g) and monoperphthalic acid (6.3 g) are kept in ether (200 ml) for several days. The sulfone, m.p. 71-72.5°, is isolated by removal of the ether, extraction with chloroform, and final recrystallization from chloroform-light petroleum or benzene-cyclohexane. 

This method is very convenient, requires relatively little time, and gives yields of 70-90%. It can be applied to condensed aromatic systems such as pyrene594 and coronene595 and to ferrocene596 and colchicine.597 Results are equally good when the alkyl dichloromethyl ether is replaced by dichloromethyl methyl sulfide.598 An example is the formylation of veratrole described below, and the same procedure can be used for preparation of mesitylenecarbaldehyde from mesitylene ... 

Di-2 methylallyl sulfide (2-Methylallyl sulfide) Chloromethyl dichloromethyl sul6de... 

Chromyl chloride Cyanogen bromide Cyanogen chloride Dibromoethyl sulfide Dichloroethyl arsine Dichloromethyl ether Diphenylchlorarsine... 

Methylthio(chloro)carbene has been generated under phase transfer conditions from dichloromethyl methyl sulfide. This carbene cyclopropanates tetramethyl-ethylene in 43%yield, accompanied by a 24%yield of l,2-dichloro-l,2-Z /5-methyl-thioethylene [24]. 

Gross and Mirsch found that reaction of aromatics with dichloro methyl methyl sulfide and aluminum chloride yield aromatic aldehydes. However, the yields were lower compared to using dichloromethyl ethers as formylating agent. Cumene aldehyde was obtained in a 41%, mesityl aldehyde in 49% and 2-naphthyl aldehyde in 52% yield (Eq 1.16). 

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