Nucleophilic Displacement of Primary Amino Groups via 1-Substituted 4-Tosylimidazoles

Article abstract of DOI:10.1021/jo00132a013

Two methods are discribed for the replacement of primary amino groups, situated either α or γ to a heterocyclic nitrogen atom, by ethoxy, alkylthio, and arylthio substituents, by Wittig reagents, and by hydrogen.Both methods involve transformation of the primary amino group into a nucleofugic pendant heterocycle.The first converts the primary amino group into a 5-phenyl-1-tetrazolyl substituent by benzoylation, formation of the imidoyl chloride, and reaction with sodium azide, while the second converts the primary amino group into a 1-(4-tosylimidazolyl) substituent by reaction with triethyl orthoformate and acid to give the (ethoxymethylene)amino derivative, which is then condensed with tosylmethyl isocyanide (TosMIC) anion.The 1-(4-tosylimidazolyl) substituent is shown to be more susceptible to nucleophilic displacement by a wider range of nucleophiles.