Thionyl chloride dimethylformamid

An excess of thionyl chloride - dimethylformamide catalyst is used to prevent formation of sulfonic anhydrides. A stoichiometric amount of thionyl chloride gives a much reduced yield. 

Other reagents used include thionyl chloride/dimethylformamide, e.g. formation of 8, and chloromethylenedimethylammonium chloride in chloroform, e.g. formation of... 

The thionyl chloride/dimethylFormamide protocol is one of the mildest and most convenient methods available. 

A simple synthesis of 1,3,5-trichloro-l A4,2,4.6-thiatriazine (1) is by treatment of sodium or tetraalkylammonium dicyanamide with thionyl chloride.910 Originally, this reaction was described in 1970 and the product was thought to be jV -chloro-A/-(chlorosulfanyl)-/V-cyano-carboximidic chloride.60 The reaction is carried out with a great excess of thionyl chloride in the presence of a catalytic amount of dimethylformamide. The first reaction step consists of the formation of the thionyl chloride-dimethylformamide complex and reaction with the dicyanamide anion. The second step is a further sulfinylation with elimination of sulfur dioxide.32... 

Dehydration with thionyl chloride-dimethylformamide Nitriles from carboxylic acid amides... 

Thionyl chloride dimethylformamide Diphosphoric acid diester monobetaines... 

Under careful temp, control, thionyl chloride-dimethylformamide is a general and convenient dehydrating agent.—E ... 

Amino-pyridazines and -pyridazinones react with monomethyl- or iV,A-dimethyl-formamide and other aliphatic amides in the presence of phosphorus trichloride, thionyl chloride, phosgene or benzenesuUonyl chloride to give mono- or di-alkylaminomethyl-eneamino derivatives. The same compounds can be prepared conveniently with A,iV-dimethylformamide dimethyl acetal in high yield (Scheme 50). 

Dimethy/su/famy/thioxanthene To a slurry of dry sodium thioxanthene-2-sulfonate (33.3 grams, 0.111 mol) in 50 ml of N,N-dimethylformamide was added thionyl chloride (14.3 grams, 0.122 mol) in divided portions. An exothermic reaction ensued with complete dissolution being effected in minutes. Treatment of the reaction mixture with crushed ice precipitated a gum which crystallized after a short period of stirring. The sulfonyl chloride was filtered, washed with water, and stirred with 100 ml of liquid dimethylamine. 

The step 1 product (3 mmol) was dissolved in 100 ml of A,A -dimethylformamide and then treated with thionyl chloride (15 mmol) and the mixture stirred at ambient temperature for 6 hours. This mixture was then treated with sulfamic acid (30 mmol) and triethylamine (30 mmol) dissolved in 15 ml of CH2CI2 and stirred at ambient temperature for 16 hours. The mixture was then concentrated at 50°C and stirred at ambient temperature for 1 hour. It was then centrifuged, the solid isolated and dissolved in 100 ml of , 7-dimethylformamide, and then passed through the cation exchange resin AMBERLYST 15JWET. Thereafter the solution was concentrated to 10 ml and precipitated in 200 ml of water. The precipitate was heated and dried in vacuum at 70°C for 24 hours and 0.68 g product isolated as a light brown powder. 

The fully aromatic diquaternary system 81 is prepared by acid ring closure of the salt (79) obtained by quaternization of 1,10-phen-anthroline with bromoacetaldehyde followed by dehydration of the resulting hydroxy diquaternary salt (80) with thionyl chloride.310,311 The salt 81 is unstable in aqueous solution above a pH of about 5.0. In the pH range 3.3-5.0 it is reduced by a one-electron transfer to the corresponding radical cation at a potential (E0) of —0.12 volt.311 Its reduction in dimethylformamide solution has also been studied.15,307 Substituted derivatives of 81 have been prepared.312... 

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