Triethylamine → [1-Benzyl-3-(benzyloxycarbonyl-isobutyl-amino)-2-hydroxy-propyl]-carbamic Acid hexahydro-furo[2,3-b]furan-3-yl Ester

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Reaction Steps

A solution of 1-benzyl-3-(benzyloxycarbonyl-isobutyl-amino)-2-hydroxy-propyl-ammonium chloride (4) (29.70 g, 72.90 mmol, 1 equiv), triethylamine (22.00 g, 220 mmol, 3 equiv) and carbonic acid 2,5-dioxo-pyrrolidin-1-yl ester hexahydro-furo-[2,3b]furan-3-yl ester (19.80 g, 73.00 mmol, 1 equiv) in 120 mL of dichlomethane were stirred at ambient temperature. Due to the incompleteness of the reaction, carbonic acid 2,5-dioxo-pyrrolidin-1-yl ester hexahydro-furo[2,3-b]furan-3-yl ester (5.00 g, 18.43 mmol) was added to the solution. The solution was stirred at room temperature for 24 h. The solution was washed twice with 300 mL of water and once with 300 mL of saturated NaHCO3 solution. The organic layer was dried on MgSO4, filtered, and evaporated to dryness to obtain the desired product as a white solid. (37.04 g, 70.34 mmol, 96.4%). LRMS (ES+): m/z 527 [M+H]+.

Provenance & Evidence