Acetic Anhydride → Acetic acid 5-benzyloxy-2-iodo-benzyl ester

Beteiligte Stoffe

Reaktionsschritte

To a well stirred solution of 3-benzyloxybenzyl alcohol (5.5 g, 25.7 mmol) in methanol (100 mL) and sodium hydrogencarbonate (8.4 g, 100 mmol) was added a 1.0 M solution of iodine monochloride in dichloromathane (30 mL) at 0° C. The reaction mixture was brought to room temperature and stirring continued for additional 1 h. The reaction mixture was concentrated and then diluted with dicholomethane (150 mL), washed with 10% aqueous sodium thiosulfate and dried (Na2SO4). The desired compound was purified by flash chromatography (silica) using 20% ethyl acetate in hexane to give 5-benzyloxy-2-iodobenzyl alcohol (6.2 g, 71% yield). The alcohol (4.2 g, 12.4 mmol) was dissolved in dichloromethane (100 mL) added acetic anhydride (2.52 g, 24.7 mmol) and catalytic amount of 4-dimethylaminopyridine. The reaction mixture was then stirred for 12 h, washed with aqueous sodium hydrogencarbonate and then dried (Na2SO4) to give acetic acid 5-benzyloxy-2-iodo-benzyl ester in quantitative yield. MS (ESI) 405 (M+Na) ; Rf=2.27.

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