Title:Microwave Assisted Hydrogenation of Pyridinecarboxylates: a Convenient Access to Valuable Scaffolds for Diversity Oriented Synthesis
Volume: 3
Issue: 2
Author(s): Serena Ferrini, Elena Cini, Elena Petricci and Maurizio Taddei
Affiliation:
Keywords:
Amines, diversity oriented synthesis, heterocycles, heterogeneous catalysis, hydrogenation, pinner reaction.
Abstract: Hydrogenation of pyridine under Microwave (MW) dielectric heating is a valuable method
for a rapid approach to piperidine synthesis. Starting from easily available pyridinecarboxylate derivatives,
aminopipecolic scaffolds were prepared and further decorated with a procedure potentially useful
for parallel synthesis. MW hydrogenation on PtO2 proceeded with high stereoselectivity and low
catalyst loading under mild conditions (80°C and 850 MPa of H2 pressure). MWs were also effective
to perform a Pinner reaction on 2-cyano-nitropyridines to obtain the corresponding methyl nitropyridine
carboxylates. A general procedure to decorate the 3-, 4-, and 5-amino-pipecolic derivatives obtained
from the pyridine hydrogenation has been also developed.