Triethylamin-mediated addition of 2-aminoethanethiol hydrochloride to chalcones: Synthesis of 3-(2-aminoethylthio)-1-(aryl)-3-(thiophen-2-yl) propan-1-ones and 5,7-diaryl-2,3,6, 7-tetrahydro-1,4-thiazepines

Meliha Burcu Gürderea*, Ali Cemal Emeça, Osman Nuri Aslana, Yakup Budaka & Mustafa Ceylanaa Department of Chemistry, Faculty of Arts and Sciences, Gaziosmanpasa University, Tokat, TurkeyCONTACT Meliha Burcu Gürdere burcu.gurdere@gop.edu.tr Department of Chemistry, Faculty of Arts and Sciences, Gaziosmanpasa University, 60250, Tokat, Turkey.Supplemental data (Experimental procedures, characterization data, and NMR spectra of all compounds) can be accessed on the publisher’s website.ABSTRACTThe triethylamin-mediated addition of 2-aminoethanethiol hydrochloride to chalcone analogs was investigated. This addition, bearing a 2-thienyl group at the 3-position, gave the only addition adduct at room temperature in 3 h, whereas the chalcones bearing the 2-furyl group at the 1-position gave an addition-cyclization product (1, 4-thiazepine) in the same conditions. The effect of the groups to the reaction was investigated by changing the 1- and 3-position groups. The chalcones bearing the 2-thienyl group at the 1-position and the others afforded the mixture of products in different ratio at rt for 0.5–24 h. Moreover, the addition–cyclization products (1,4-thiazepine) were obtained under reflux conditions in 36 h. The structures of the synthesized compounds were elucidated by 1H NMR, 13C NMR, infrared, and elemental analysis.