Phenylcarbamoylation of N-Acetyl-1,2,4-triazolium-4-aminides Revisited
摘要:
The reaction of N-acetyl-1,2,4-triazolium-4-aminides (I, i.e. 1Aa-d) with phenyl isocyanate affords ring functionalized products (4a-d) rather than linear adducts (II). Analogous compounds are obtained from the triazolium-1-aminide (1Ae) and the imidazolium congener (W). Twofold carbamoylation to give products of type (8) occurs on reaction of aminotriazolium salts (7A) in the presence of base. Azoliums having methyl at C(5)/(2) are inert throughout (B series).