Title: 2-Naphthol-pyrazole conjugates as substrates in the Mannich reaction.
Authors: Roman, Gheorghe
Abstract: Several novel 2-naphthol-pyrazole conjugates have been synthesized through the O-alkylation of 1-[(3,5-dimethyl-1H-pyrazol-1-yl)methyl]naphthalen-2-ol with methyl iodide, benzyl chloride, methyl bromoacetate and N-benzyl-2-bromoacetamide. The aminomethylation of these 2-naphthol-pyrazole conjugates has been examined employing the classical conditions for the Mannich reaction, and also by using N,N-dimethylmethyleneiminium chloride as preformed aminomethylating reagent. In both situations, aminomethylation of these substrates occurred at C-4 of the pyrazole ring. The bifunctional substrate 1-[(3,5-dimethyl-1H-pyrazol-1-yl)methyl]naphthalen-2-ol has been chemoselectively aminomethylated in the pyrazole ring using the same preformed aminomethylating reagent.
Subjects: NAPHTHOL; PYRAZOLES; METHYL iodide; BENZYL chloride; CHEMOSELECTIVITY; MANNICH reaction
Publication: Zeitschrift für Naturforschung B: A Journal of Chemical Sciences, 2018, Vol 73, Issue 5, p275
ISSN: 0932-0776
Publication type: Academic Journal
DOI: 10.1515/znb-2017-0209

2-Naphthol-pyrazole conjugates as substrates in the Mannich reaction.

Roman, Gheorghe