Iodine → 2-(4'-Chlorophenyl)-2-methyl-1,3-dithiolane

Participants

Reaction Steps

A mixture of 4-chloroacetophenone (1.3 mL, 10 mmol), iodine (250 mg, 1 mmol), 1,2-ethanedithiol (0.85 mL, 10 mmol) in dry tetrahydrofuran (20 mL) was heated at reflux under an atmosphere of nitrogen for 16 h. The mixture was allowed to cool to room temperature and concentrated in vacuo and the residue taken up in ether (20 mL). The organic solution was washed with water (2×10 mL) and brine (1×10 mL), then dried (Na2SO4) and evaporated under reduced pressure. Flash column chromatography of the residue, eluting with 37% aqueous ammonia:ether:hexane (0.02:1:6) afforded 2-(4-chlorophenyl)-2-methyl-1,3-dithiolane (24) as a colourless oil (1.11 g, 48%). 1H nmr (300 MHz, CDCl3) 2.13 (s, 3H, CH3), 3.31-3.53 (m, 4H, SCH2CH2S), 7.27 (d, J=8.7 Hz, 2H, 2×ArH), 7.69 (d, J=8.7 Hz, 2H, 2×ArH).

Provenance & Evidence