Catalytic activity of vanadyl acetate in the acetylation of secondary alcohols

Abstract

The synthesis of esters (acetates) from alcohols through selective
ways is of great importance taking into account a synthetic pharmacological
and technological points of view, because the protection of hydroxy
groups in the molecule allows to develop structural transformations in the
starting alcohol, obtaining new derivatives with potential biological and industrial
properties. In this work ,the synthesis of esters (acetates) is carried
out by means of heterogeneous catalysis in liquid phase using a Lewiss
acid catalyst vanadyl acetate [VO(AcO)2] in an apolar aprotic solvent (chloroform).
This heterogeneous catalytic system is used for the first time for
obtaining esters (acetoxy derivatives) in ecological friendly conditions avoiding
use of pyridine and its alquil derivatives, without generating secondary
undesirable processes, with satisfactory yield (> 70 %) of esters. Of great
methodological significance is the possibility of re-utilization of the catalyst
(vanadyl acetate) after separation from the reaction mixture by filtration
dryness and thermal activation at 50 oC during 1 h . All compounds
were properly elucidated using spectroscopic techniques (FTIR, H-NMR,
13C-NMR).