Activation of Electrophilicity of Stable Y-Delocalized Carbamate Cations in Intramolecular Aromatic Substitution Reaction: Evidence for Formation of Diprotonated …
Although cations with three heteroatoms, such as monoprotonated guanidine and urea, are stabilized by Y-shaped conjugation and such Y-conjugated cations are sufficiently basic to be further protonated (or protosolvated) to dications in strongly acid media, only O- monoprotonated species have been detected in the case of carbamates even in magic acid. We found that the trifluoromethanesulfonic acid-catalyzed cyclization of ...
![methyl N-[2-(4-methoxyphenyl)ethyl]carbamate结构式](https://image.chemsrc.com/caspic/110/91247-71-1.png)
![methyl N-[2-(4-hydroxyphenyl)ethyl]carbamate结构式](https://image.chemsrc.com/caspic/179/62372-08-1.png)
