Thermic and photochemical study of new (trifluoromethyl)-sulfonyl dihydropyridin carboxilic ácid and lactones

FIRPO, GUADALUPE; PELAEZ, WALTER J.; CHANS, GUILLERMO M.; RIVERA-HERNANDEZ, ALEJANDRO; ALVAREZ TOLEDANO, CECILIO; ARGÜELLO, GUSTAVO

Villa Carlos Paz

Conferencia; 13a Conferencia Latinoamericana de Fisico-Química Orgánica; 2015

INFIQC, Universidad Nacional de Córdoba, Argentina

Pyridines emerge as one of the most prevalent heterocyclic structural units in pharmaceutical and agrochemical targets, as well as in material science. Pyridine derivatives are widely known as gifted starting materials for the synthesis of di- and tetrahydropyridines, which have been used as intermediates in alkaloid synthesis, and as important biologically active structures. It is known that one key aspect about the reactivity of pyridine and its derivatives is that once activated, they can react with a large variety of nucleophiles to afford substituted dihydropyridines, which can further be reactivated to undergo secondary nucleophilic additions. In this work, we present the thermic and photochemical study of the title compounds aiming at performing the re-aromatization reaction of these dihydro-heterocycles as a new synthetic methodology of pyridine derivatives. The reaction were performed into a photolysis equipment using a Hg lamp (λ=254nm) in ACN as solvent and followed by UV spectroscopy. Static pyrolyses were performed using a tube furnace with a temperature-controller device. The substrate was introduced into a reaction tube (1.5cm×12cm Pyrex), sealed under vacuum (0.06 mbar) and then placed into the reactor during 5-20 min at 200◦C.