1,2,4,6-Thiatriazine 1,1-dioxides synthesis

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... 

A simple, efficient synthesis of 4-substituted 1,2,4,6-thiatriazine 1,1-dioxides involves reacting 0,0 -diaryl carbonimidates with thionyl chloride and triethylamine to give sulfoxides which are oxidized with MCPBA. The resulting sulfamides are then reacted with primary amines to give the required products (Scheme 9) <87S170>. 

Diphenyl A-sulfamoylcarbonimidate (54) is a useful reagent for the synthesis of heterocyclic S-oxides, including 1,2,4,6-thiatriazine 1,1-dioxides (Scheme 10) <91S753>. 

The synthesis of 4H- and A4-amino-l,2,4,6-thiatriazine 1,1-dioxides 137 and 165 was achieved from the dithio-imidocarbonate 230 (Scheme 43). One of the two moles of 230 captured HCI released during formation of 231 and this procedure was higher yielding than with triethylamine as the base. The ammonium salt 23TNH4 was prepared from 231 with ammonia in THE or acetonitrile at 0°C <1996H(43)2199>. 

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See also in sourсe #XX -- [ , , ]

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