Iodine → ethyl (NZ)-N-(4-butyl-2-tert-butyl-1,2-thiazol-5-ylidene)carbamate

Participants

Reaction Steps

To a solution of Example 1A (4.2 g, 27 mmol) in THF (100 mL) at room temperature under N2 was added O-ethyl carbonisothiocyanatidate (3.55 g, 27 mmol). The reaction mixture was stirred for 1 hour and iodine (6.8 g, 27 mmol), MeOH (100 mL) and pyridine (10 mL) were added. The reaction mixture was stirred for 2 hours. The reaction mixture was poured into saturated NaHCO3/Et2O and stirred for 30 minutes. Additional saturated NaHCO3 and Et2O were added and the organic layer was separated. The aqueous layer was extracted with Et2O (2×) and combined organics were dried (MgSO4) and concentrated in vacuo. Toluene and acetonitrile were added and evaporated to remove water and pyridine. The crude compound was purified by flash chromatography using 0-100% EtOAc in hexane as eluent to give 5.2 g of the title compound as yellow solid. 1H NMR (300 MHz, CDCl3) δ ppm 0.93 (t, J=7.3 Hz, 3 H), 1.27-1.47 (m, 5 H), 1.54-1.73 (m, 11 H), 2.59-2.74 (m, 2 H), 4.28 (q, J=7.1 Hz, 2 H), 7.78 (s, 1 H). MS (DCI/NH3) m/z 285 (M+H)+.

Provenance & Evidence