Ethyl Acetate → 3-Hydroxymethyl-6,7-dihydropyrido[3,2-b]thieno[2,3-d]oxepine

Participants

Reaction Conditions

Reaction Steps

To a solution of 1.00 M of diisobutylaluminum hydride in toluene (4.02 mL) at 0° C. was added 3-methylcarboxy-6,7-dihydropyrido[3,2-b]thieno[2,3-d]oxepine (0.420 g, 1.61 mmol) in toluene (17.8 mL, 167 mmol). The reaction mixture was stirred at 0° C. 2 h. The reaction is diluted with EtOAc then quenched with 1M HCl. The organic layer was dried Na2SO4, concentrated to give 3-hydroxymethyl-6,7-dihydropyrido[3,2-b]thieno[2,3-d]oxepine which was dissolved in triethylamine (0.336 mL, 2.41 mmol) and N,N-dimethylformamide (10.5 mL, 136 mmol). Tert-butyldimethylsilyl chloride (0.291 g, 1.93 mmol) was added. The reaction was stirred at room temperature 20 min. The reaction was diluted with EtOAc then wash with water and brine, dried and concentrated to give 3-tert-butyldimethylsilyloxymethyl-6,7-dihydropyrido[3,2-b]thieno[2,3-d]oxepine which was dissolved in DCM/Acetic acid at 0° C. N-Bromosuccinimide (315 mg, 1.77 mmol) was added. The reaction was stirred overnight at room temperature. The reaction was concentrated and purified by flash chromatography (EtOAc/Hex) (eluted 10%) to give 3-tert-butyldimethylsilyloxymethyl-9-bromo-6,7-dihydropyrido[3,2-b]thieno[2,3-d]oxepine (61.3% yield). MS: (ESI+) 426.1

Provenance & Evidence