Reaction between Chalcones, 1,3-Dicarbonyl Compounds, and Elemental Sulfur: A One-Pot Three-Component Synthesis of Substituted Thiophenes

Abstract

A simple and atom-economic synthesis of highly substituted thiophenes is demonstrated. Heating a solution of a chalcone and a ­linear/cyclic 1,3-dicarbonyl compound with elemental sulfur in CH3CN in the presence of NEt3 at 80 °C afforded the corresponding substituted thiophenes in good to excellent yields.

Recent Advances in the Synthesis of Heterocycles via Reactions Involving Elemental Sulfur

“…The combination of aromatic aldehydes and phenacyl bromides could be replaced by chalcones 17 as a unique component (Scheme 6). [6] In this case, the first step was a Michael addition of 1,3-diketone or βketoester 18 to chalcones 17 catalyzed by triethylamines whereas the second step followed exactly the same pathway.…”

l-Proline-Catalyzed Three-Component Reaction of 4-Chloro-3-formylcoumarin, Sodium Sulfide, and α-Halo Ketones: A Direct Approach to Thieno[3,2-c]coumarins

“…40 Thieno[3,2- c ]coumarins have also been prepared by the reaction of chalcones with 4-hydroxycoumarin and elemental sulfur. 41 4-Mercaptocoumarin has also been used as a building block for thienocoumarins through a thio-Claisen rearrangement. 42 Thieno[3,2- c ]coumarins have also been prepared by the reaction of 4-chloro-3-formylcoumarin with a thioglycolate and 1,4-dithiane-2,5-diol or a combination of sodium sulfide and chloroacetaldehyde.…”

“…40 Thieno [3,2-c]coumarins have also been prepared by the reaction of chalcones with 4-hydroxycoumarin and elemental sulfur. 41 4-Mercaptocoumarin has also been used as B V. Thotathil et al…”

Synthesis of 4,5-dihydro-1H-pyrazole derivatives based on 3-acetyl-5-nitropyridines

“…For example, reactions of chalcones with binucleophiles are used in preparation of 4,5-dihydro-1H-pyrazoles [11,12], as well as pyrimidines, pyridines, etc. [13][14][15]. 4,5-Dihydro-1H-pyrazole derivatives have luminescent properties [16] and also exhibit antibacterial [17], antioxidant [18], analgesic [19], anti-in ammatory [20], and antimycobacterial activity [21].…”