Despite its low nucleophilicity 2,6-di-tert-butylpyridine (D TBP) easily undergoes N-amination. Other hidered pyridines react similarly. Comparison of the NMR carbon chemical shifts of 2,6-disubstituted 1-aminopyridinium perchlorates and those of the respective 1-methylpyridinium salts shows that the changes are parallel. 1-Amino-2,6-di-tert-butylpyridinium perchlorate does not react with p-dimethylaminobenzaldehyde. However, other hindered 1-(4'-dimethylaminobenzylideneamino)pyridinium salts were obtained by a standard procedure.
Despite its low nucleophilicity 2,6-di-tert-butylpyridine (D TBP) easily undergoes N-amination. Other hidered pyridines react similarly. Comparison of the NMR carbon chemical shifts of 2,6-disubstituted 1-aminopyridinium perchlorates and those of the respective 1-methylpyridinium salts shows that the changes are parallel. 1-Amino-2,6-di-tert-butylpyridinium perchlorate does not react with p-dimethylaminobenzaldehyde. However, other hindered 1-(4'-dimethylaminobenzylideneamino)pyridinium salts were obtained by a standard procedure.