Sodium hydride → HCID 71245505, compound

Participants

Reaction Steps

150 mg (3.75 mmol, 60% in mineral oil) of sodium hydride were suspended under nitrogen atmosphere in 2 m dry dimethyl acetamide. 488 mg (1.5 mmol) of ethyl 4-benzyl-6-hydroxychroman-3-ylcarbamate dissolved in 8 ml dry dimethyl acetamide were added dropwise at room temperature and stirred for 1 h. Then 1.0 g (4.47 mmol) of tert-butyl 2-bromoethylcarbamate dissolved in 2 ml acetate amide were added slowly. The reaction mixture was allowed to warm to room temperature and stirred for 84 h. Then additional 50 mg (1.4 mmol) sodium hydride were added and the mixture was stirred for 30 min before additional 350 mg of tert-butyl 2-bromoethylcarbamate were added and the mixture was stirred for additional 72 h. The reaction mixture was poured onto diluted sodium hydrogencarbonate solution and extracted with ether (2×). The combined organic phases were washed with water (2×), dried over MgSO4 and concentrated (1.5 g of crude). The crude material was purified by flash chromatography to give 587 mg (1.25 mmol, 84%) of the desired product.

Provenance & Evidence