1,1'-Carbonyldiimidazole → (3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-yl-N-[(1S,2R)-3-chloro-1-benzyl-2-hydroxypropyl]carbamate

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Reaction Steps

1,1′-carbonyldiimidazole (162.15 g, 1 mol) was added to THF (0.5 L), following by solution of (3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-ol (135.2 g, 1.04 mol) in 0.3 L of THF and the mixture was stirred for a further hour. (2S,3S)-3-amino-1-chloro-2-hydroxy-4-phenylbutane hydrochloride (229 g, 0.97 mol) was added and the mixture heated at 55-60° C. approximately 5-6 hours under TLC control (for complete disappearance of (2S,3S)-3-amino-1-chloro-2-hydroxy-4-phenylbutane). After completion of reaction the solution was cooled and transformed to the next step. For the preparation of analytical sample, 10 ml of solution was diluted with 50 ml of ethyl acetate, washed with water (40 mL), diluted hydrochloric acid (40 ml), 5% aqueous sodium hydrogen carbonate (40 mL) and water (50 mL). The solution was dried over sodium sulfate and evaporated to dryness. MS: m/z 356 (MH+). NMR spectrum corresponded to the structure of the desired product.

Provenance & Evidence