4-Methylquinoline → Tert-butyl 3-(4-methylquinolin-2-yl)azetidine-1-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

H2O2 (30% in H2O; 0.31 mL, 3.0 mmol) was added to a stirred solution of lepidine 1a (132 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 60 min, then poured into a 0.2 M solution of NaOH (30 mL) and Et2O (50 - 12 -mL). The aqueous and organic layers were partitioned and the organic layer was washed with H2O (1 x 30 mL) and brine (1 x 30 mL), then 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 (3:7) as eluent to give the desired product 3a (90 mg, 30%) as a solid and a 9:1 mixture of lepidine 1aand desired product 3a (58 mg).

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