Dicyanogen triselenide

In addition to the wide variety of primary, secondary and tertiary alkyl aryl sulfides, selenides and tellurides which can be prepared by this method, the Barton group also developed concise syntheses of two of the most important selenoamino acids, L-selenomethionine and L-selenocystine using this approach [18] (Scheme 13). The use of crystalline dicyanogen triselenide for introduction of the selenocyanate moiety is also very useful. 

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