Sodium Carbonate → 1,1-Dioxo-3-butyl-3-ethyl-5-phenyl-7-bromo-8-(1-ethoxycarbonylethoxy)-2,3,4,5-tetrahydro-1,5-benzothiazepine

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Reaction Steps

Sodium carbonate (0.30 g, 2.83 mmol), 2-bromopropanoic acid ethyl ester (0.145 g, 0.796 mmol) and tetrabutylammonium bromide (0.022 g, 0.07 mmol) was added to a solution of 1,1-dioxo-3-butyl-3-ethyl-5-phenyl-7-bromo-8-hydroxy-2,3,4,5-tetrahydro-1,5-benzothiazepine (WO 96/16051; 0.300 g, 0.663 mmol) in MeCN (10 ml). The suspension was heated under reflux over night. The solvent was evaporated and the crude mixture was extracted (DCM/H2O), dried (MgSO4), evaporated and purified by flash chromatography (Hex:EtOAc-5:1) to give the title compound 0.346 g (95%) as a white solid. NM (400 MHz) 0.70-0.85 (m, 6H), 1.00-1.75 (m, 8H), 1.35 (t, 3H), 1.70 (d, 3H), 3.05-3.25 (m, 2H), 3.55-3.90 (m, 2H), 4.20-4.35 (m, 2H), 4.80 (q, 1H), 7.00-7.10 (m, 3H), 7.15 (s, 1H), 7.25-7.35 (m, 2H), 7.45 (s, 1H).

Provenance & Evidence