Silver cyanide isocyanide synthesis

Imidazolines are also formed in silver cyanide-catalyzed cyclization of alkyl isocyanides with aliphatic diamines (Scheme 103).169 This simple synthesis can be applied in a general way with difunctional nucleophiles and has been used to prepare benzimidazoles, oxazoles, thiazoles, and oxazines.169 It is suggested that transient carbene complexes are formed in these reactions (cf. 87 in Scheme 103) but further work is required to ascertain the mechanism and scope of these processes. 

The scope of the silver cyanide-catalyzed reaction of difunctional nucleophiles with alkyl isocyanides has been described in the earlier section on imidazoles an example of the use of this simple approach in benzimidazole synthesis is illustrated in Scheme 105.169... 

Silver cyanide, reaction with alkyl halides in synthesis of isocyanides, 46, 77... 

Silicon tetraisothiocyanate, reaction with 2,6-dimethylaniline to yield 2,6-diraethylphenyl thiourea, 46, 70 Silver cyanide, reaction with alkyl halides in synthesis of isocyanides, 46, 77... 

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