Triethylamine → N-(2,4-dibromophenyl)-3-hydroxyazetidine-1-carbothioamide
Reaction equation
[Br:1][C:2]1[CH:7]=[C:6]([Br:8])[CH:5]=[CH:4][C:3]=1[N:9]=[C:10]=[S:11].Cl.[OH:13][CH:14]1[CH2:17][NH:16][CH2:15]1.C(N(CC)CC)C>C(#N)C>[Br:1][C:2]1[CH:7]=[C:6]([Br:8])[CH:5]=[CH:4][C:3]=1[NH:9][C:10]([N:16]1[CH2:17][CH:14]([OH:13])[CH2:15]1)=[S:11]Participants
5
Procedure
2,4-Dibromophenylisothiocyanate (CAS#13037-63-3, 3.02 g, 0.0103 mole), and 3-hydroxyazetidine hydrochloride (CAS#18621-18-6, 1.18 g, 10.8 mmol) were suspended in acetonitrile (35 mL). Triethylamine (1.53 mL, 0.011 mole) was added dropwise to the stirred suspension. After 20 minutes of stirring at room temperature, the reaction mixture had become a light yellow solution. After another 10 minutes of stirring at room temperature, the isothiocyanate was consumed and the intermediate, N-(2,4-dibromophenyl)-3-hydroxyazetidine-1-carbothioamide had formed. Although not necessary, this intermediate thiourea was isolated and purified by partitioning between 1:1 hexane/ethyl acetate (150 mL) and 1 M aqueous KH2PO4 (35 mL). The organic layer was washed with saturated aqueous sodium bicarbonate (10 mL) and dried (Na2SO4). The filtrate was partially concentrated at which point the thiourea crystallized. The crystals were collected by filtration and dried under vacuum to provide N-(2,4-dibromophenyl)-3-hydroxyazetidine-1-carbothioamide.