چكيده فارسي :
Perhalogenated aromatic and heteroaromatic compounds are important starting materials
for synthesis of other heterocyclic and macrocyclic compounds [1,2].Polychloroheterocycles
played an important role in the synthesis of the corresponding polyfluorocomponds. For
example, pentachloropyridine used as intermediates for synthesis of other useful material such
as pentafluoropyridine. Pentachloropyridine reacted with larger nucleophiles at 2-position of
pyridine ring and with small nucleophiles at 4-position of pyridine ring. However, the
outcome of nucleophilic substitution on pentachloropyridine is not as clear-cut as it seems at
first sight. Therefore, substitution reactions are often solvent dependent [3].
In this work we investigated the reaction of pentachloropyridinewithbis(dithiocarbamate
salt) and 3,4-dihydropyrimidine-2(1H)-thione derivatives. Dithiocarbamate salt of amines can
be prepared according to the procedure given in literature [4,5]. Reaction of Dithiocarbamate
saltand 3,4-dihydropyrimidine-2(1H)-thione derivatives with pentachloropyridinegave
products rising from the substitution of the most activated chlorine atom at the 4-position of
pyridine ring (figure 1, 2). Products confirmed by 1H-NMR and 13C-NMR spectroscopy data.
