Sulfur triimides

The tetraimidosulfate anion [S(NtBu)4] , isoelectronic with 804 , is prepared by a methodology similar to that employed for the synthesis of triimidosulfites. The reaction of the sulfur triimide S(N Bu)3 with two equivalents of LiNH Bu produces the solvated monomeric complex [(thf)4Li2S(N Bu)4] (10.21) (Eq. 10.8). The nucleophilic addition of... 

The reaction of sulfur t-butyltriimides 87 with fluoro- orchlorosulfonyl isocyanate results in an exchange reaction giving rise to the formation of t-butyl isocyanate and another sulfur triimide 88 ". ... 

When the reaction is conducted using excess sulfonyl isocyanate, the [2+2] cycloadducts 89, derived from a different sulfur triimide and t-butyl isocyanate, are isolated. 

Cycloaddition across the S=N bonds in perfluorosulfinylamines and in sulfur triimides to give cyclodiaza-k -thianes 91 is also observed. 

The formal replacement of a sulfur atom in cyclo-S generates S7NH (6.1), the first member of a series of cyclic sulfur imides that includes the three diimides 1,3-, 1,4-, and 1,5-S6(NH)2 (6.2-6.4), two triimides 1,3,5-and 1,3,6-S5(NH)3, and S4N4H4 (6.5). Isomers of these ring systems containing adjacent NH groups are not known. 

The cyclic sulfur imides are odorless, nearly colorless solids. All are well crystallized the 1,3,5-triimide appears as fine needles, w hereas all the others are orthorhombic crystals... 

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