Study of the effect of solvent and different Lewis acids in one pot multicomponent microwave assisted reaction for the chemoselective generation of 1.4-thiazepan-3-ones and 4-thiazolidinones

ALDANA A. QUIROGA; IGNACIO O. COSTILLA; FERNANDO J. LORENZO; JUANJO CALMELS ; DANIELA P. VILLAFAIN; SANDRA D. MANDOLESI; NORMA B. DACCORSO ; ROMINA A. OCAMPO

Basel

Conferencia; The 21st International Electronic Conference on Synthetic Organic Chemistry (ECSOC-21); 2017

Sciforum (ECSOC-21)

With the aim of exploringthe best reaction conditions for the diastereoselective synthesis of the 1,4?thiazepan-3-ones(4)and 4 -thiazolidinones(5), we  havestudied the effect on solvent variation  and the aggregation of AlCl3 and differentzeolites as Lewis acid catalysts to the three-component microwave assistedreaction between 2,3:4,5-di-O-isopropylidene-b-D- arabino-hexos-2-ulo-2,6-pyranose(1),benzotiazole(3) and thioglycolic acid (2). Based on the results of previous studies of ourgroup, we discuss here two microwave assisted methods: multicomponent reaction inthe presence of the catalysts (Method A) and sequential reaction with generationof the corresponding intermediate s and subsequent addition of the catalysts coordinatedto thioglycolic acid (Method B).