Pyridine → ((2S,4R)-4,5-diacetoxy-4-methyl-tetrahydrofuran-2-yl)methyl benzoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 3.8 g of ((5S,6aR)-2,2,6a-trimethyl-dihydro-5H-furo[3,2-d][1,3]dioxol-5-yl)methyl benzoate (from step 9) in 25 mL of 70% acetic acid was heated to 70° C. for 48 h. The reaction mixture was diluted with ethyl acetate and washed with water and saturated NaHCO3. The organic layers were dried over anhydrous Na2SO4, filtered and concentrated. Crude diol obtained was aceylated using Ac2O (0.03373 mol, 3.18 mL) and 20 mL of anhydrous pyridine with catalytic amount of DMAP (5 mol %). The progress of the reaction was monitored by TLC. Pyridine was removed under vacuum and the residue was diluted with ethyl acetate and was washed with 1N HCl and saturated NaHCO3. The organic layers were dried over anhydrous Na2SO4, filtered and concentrated. Purified by column chromatography to give 3.3 g of the title compound (88% yield) and 0.55 g of starting material acetonide was recovered.

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