Ultrasonics promoted synthesis of thiazolidinones from 2-aminopyridine and 2-picolilamine

Abstract

The efficient multicomponent synthesis of thiazolidinones from the reaction of arenealdehydes, mercaptoacetic acid and 2-picolilamine or 2-aminopyridine under ultrasound irradiation are reported. The reaction with 2-aminopyridine needs a Lewis acid catalysis to afford the corresponding 2-aryl-3-(pyridin-2-yl)-1,3-thiazolidin-4-ones. All novel compounds were identified and characterized by (1)H and (13)C NMR spectra. Applying the sonochemical methodology, two series of heterocyclic thiazolidinones were synthesized in good yields after short reaction times.

Synthesis and identification by GC-MS of 3-(pyridin-2-yl)- thiazolidinethiones

“…For the synthesis of thiazolidinones 3a-h was utilized ultrasonic irradiation methodology according Gouvea et al 1 The proposed substances 4a-h were obtained with considerable yield in two steps as shown in Squeme 1 through addition 0,5 mmol 3a-h, 1 mmol Lawesson's reagent in dry toluene (25 mL), and the reaction mixture was refluxed with stirring for 12 h (monitored by TLC). The characterization of 3a-h and 4a-h was performed by GC-MS, considering that the confirmation by 1 H and 13 C NMR has only been done with compounds 3a-h. Squeme 1.…”

“…The characterization of 3a-h and 4a-h was performed by GC-MS, considering that the confirmation by 1 H and 13 C NMR has only been done with compounds 3a-h. Squeme 1. …”

“…1 Transformation of a carbonyl functional group into thiocarbonyl has been an important interest to synthetic organic chemists for many years. Lawesson's Reagent is the most widely used agent for such a transformation.…”

Efficient synthesis via molecular sieve of 3-(pyrimidin-2yl)- thiazolidinones

“…Moreover, high temperature (~80ºC) an BF 3 addition increased the efficiency of the reactions with molecular sieve, similar that reported by Gouvêa et al under azeotropic distillation. 3 The proposed compounds, 4a-k, were obtained in two steps as show in Scheme 1. The progress of reactions was monitored by GC and TLC, and the compounds were confirmed by GC-MS and melting point determination.…”

Ultrasonics promoted synthesis of thiazolidinones from 2- aminopyridine

“…Our research group has been studied non-conventional methodologies for the synthesis of thiazolidinones. 2 Ultrasound irradiation has been utilized to accelerate a number of synthetically useful reactions during the last few years 3 . In continuation of our studies, the aim of this paper is the sonocatalysis synthesis of thiazolidinones from the cyclocondensation reaction of 2-aminopyridine, arenealdehydes and mercaptoacetic acid.…”