Sulfur-nitrogen anions

T. Chivers and R. T. Oakley, Sulfur-Nitrogen Anions and Related Compounds, Topics Curr. Chem., 102, 119 (1982). 

Sulfur—nitrogen anions in sulfur—liquid ammonia solutions... 

Role of Sulfur-Nitrogen Anions in the Synthesis of Cyclic Sulfur... 

Structurally characterized since 1970 and the structure of the eighth (S4N3 ) has been redetermined recently b) the first binary sulfur-nitrogen anion, S N " was isolated in 1975 and its structure was reported a year later c) the novel sulfur nitride, SjNg, was first identified in 1978 and d) although tetrasulfur dinitride, S N, has been known since 1897, the structure was not unequivocally determined until 1981... 

The cyclic sulfur imides S NH and 1,3-, 1,4-, and l,5-S(j(NH)2 are obtained by acid hydrolysis of the deep blue intermediate formed from the reaction of SjClj with ammonia in polar solvents, e.g. DMF or by the reaction of sodium azide with elemental sulfur in HMPA The blue chromophore formed in both these reactions is S4N and it has therefore been suggested that this anion is involved in equilibria with cyclic sulfur-nitrogen anions which are the precursors of the imides... 

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