Acetyl chloride → HCID 86596474, compound

Participants

Reaction Conditions

Reaction Steps

Acetyl chloride (75 ml; 1.05 mole) was added drop-wise with stirring to methanol (7500 ml) at 0–5° C. under nitrogen. The mixture was stirred at this temperature for a further 15 minutes then held at approximately 10° C. as (2R,3R,4S)-3-(acetylamino)4-amino-2-[(1R,2R)-1,2,3-trihydroxypropyl]-3,4-dihydro-2H-pyran-6-carboxylic acid trihydrate (see J. Med. Chem. 1998, 41, 787–797) (250 g; 726 mmoles) was added in portions. The mixture was stirred at approximately 60° C. for 5 hours then cooled to approximately 20° C. and stirred at this temperature overnight. The solvent was removed and the residue twice evaporated down again with methanol (2×500 ml) to give a mixture of a foam and gum. This was re-dissolved in methanol (˜1000 ml), evaporated and the residue then triturated with DCM and re-evaporated. The trituration DCM process was repeated. The residue was dried overnight in a vacuum-oven at approximately 30° C., crushed and then dried overnight again to give Intermediate 2 as a white powder (264.2 g).

Provenance & Evidence