Chemoselective aminomethylation of bifunctional substrates: carbonyl versus phenolic hydroxyl, carbonyl versus pyrazole and pyrrole versus phenolic hydroxyl as competing activating groups
作者:Gheorghe Roman
DOI:10.1016/j.tetlet.2014.01.005
日期:2014.2
Chemoselectivity in the Mannich reaction for three different types of bifunctional substrates has been investigated. 1-Hydroxy-2-naphthalenylethanone affords either phenolic Mannichbases at high pH (free amines), or ketonic Mannichbases at low pH (amine hydrochlorides), whereas the use of N,N-dimethylmethyleneiminium chloride as a preformed dimethylaminomethylation reagent gave the phenolic Mannich base. 1-Ar