Benzothiazole → 3-Benzothiazol-2-yl-azetidine-1-carboxylic acid tert-butyl ester

참여 물질

반응 조건

반응 단계

H2O2 (30% in H2O; 0.31 mL, 3.0 mmol) was added to a stirred solution of benzothiazole 1f (108 μL, 1.0 mmol), concentrated H2SO4 (53 μL, 1.0 mmol), 1-Boc-3-(iodo)azetidine (849 mg, 3.0 mmol) and iron(II) sulfate heptahydrate (80 mg, 0.3 mmol) in DMSO (10 mL) at room temperature. After 1-2 min a further portion of iron(II) sulfate heptahydrate (80 mg, 0.3 mmol) was added and the mixture was stirred at room temperature for 30 min. Further H2O2 (0.31 mL, 3.0 mmol) and iron(II) sulfate heptahydrate (80 mg, 0.3 mmol) was added, and the mixture was stirred for overnight, then poured into a 0.2 M solution of NaOH (30 mL) and EtOAc (50 mL). The aqueous and organic layers were partitioned and the organic layer was dried (MgSO4), filtered and the solvent removed under vacuum to leave a crude oil. The oil was purified by preparative thin-layer chromatography using EtOAc / hexanes (1:4) as eluent to give a mixture of recovered benzothiazole 1f and 1-BOC-3-(iodo)azetidine, and the desired product 3e (45 mg, 15%)

출처 및 근거