Sulfur trioxide, reaction with cyanogen

Sulfur trioxide, reaction with cyanogen chloride, 46, 24... 

I-Cyanobenzocyclobctene, 48, 53 8-Cyanoethylhydrazine, from acrylonitrile and hydrazine, 48, 8 reaction with sulfuric acid, 48, 8 Cyanogen bromide, 45, 88 Cyahogen chloride, in preparation of chlorosulfonyl isocyanate, 46, 24 reaction with sulfur trioxide, 46, 24 7-Cvanoheptanal, 49, 27, 28... 

An analogous product (252 X = Cl) is formed in the reaction of sulfur trioxide with cyanogen chloride (68AG(E)172). Aryl cyanates also condense with sulfur trioxide to give 1,2,3,5-oxathiadiazines analogous to those formed from dialkylcyanamides (67CB3736). 

Chlorosulfonyl isocyanate6 (CSI) (57) is a very reactive compound which was first prepared from cyanogen chloride (56) and sulfur trioxide (Graf, 1956) (Scheme 31). CSI (57) undergoes [2+2] cycloaddition reactions with various alkenes initial adducts like (58) and (59) may be hydrolysed to the b-lactams (60) and (61). The cycloaddition reaction also occurs with enamines (62) to give products like (63) and (64) (Scheme 32). 

Reaction of sulfur trioxide with cyanogen chloride at a temperature not exceeding O C results in the formation of CSI and the 1,4,3,5-oxathiadiazine... 

An interesting and almost quantitative formation of sulfuryl amide is based on the use of sulfuryl diisocyanate (LXXXII), which can be made by the action of cyanogen bromide on sulfur trioxide (60), or by the reaction of chlorosulfonyl isocyanate (LXXXI), with silver cyanate (3). 

EXPLOSION and FIRE CONCERNS not combustible, but extremely irritating if involved in a fire combination with water evolves heat NFPA rating Health 4, Flammability 0, Reactivity 1 reacts explosively with cyanogen fluoride, glycerol and nitric acid, and methane-sulfonic acid violent reaction with acetic anhydride, 2-aminoethanol, chlorosulfonic acid, ethylene diamine, propylene oxide, vinyl acetate, sodium hydroxide, and sulfuric acid liquid hydrogen fluoride reacts incandescently with arsenic trioxide and calcium oxide reacts with water or steam to produce toxic and corrosive fumes incompatible with most metals, water and alkali... 

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