Hi,
Nguoi ta ko este hoa glucose bang xuc tac H2SO4 dau ban a. Vi hieu suat thap. Minh xin gui ban qua trinh tong hop nhe.
The compound pentaacetyl D-glucopyranose was synthesised as the method of 1. To a solution of D-glucose (3 gam, 16.65 mmol) in dry pyridine (33 ml) at 00 C under N2 was slowly added acetic anhydride (31.5 ml, 333 mmol). The reaction mixture was stirred at 00 C for 1h before a catalytic amount of DMAP (200 mg, 1.67 mmol) was added. As the reaction mixture was allowed to reach rt, the reaction become slightly exothermic. After 6h, the clear yellow mixture was slowly poured into 500 ml of fast stirring ice-water, giving a sticky solid. After ethyl acetate extraction (3 x 45 ml), evaporation of the solvent and co-evaporations with dry toluene (3x20 ml) acetyled glucose was obtained as a yellow solid (5.84 gam, 90%).
Chuc ban thanh cong
Than ai,
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