Hydrochloric Acid → HCID 118045321, compound

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Reaction Steps

To a temperature controlled stirred reactor charge cerium (III) chloride heptahydrate (4.55 moles; 1.12 kg) in ethanol (4.96 L) and stir to give a solution. Add [(2R,3R,4S,5R,6R)-3,4,5-triacetoxy-6-[3-(4-benzyloxybenzoyl)-4-methyl-indol-1-yl]tetrahydropyran-2-yl]methyl acetate (1.52 moles; 1.38 kg) and tetrahydrofuran (7.57 L). Cool the mixture to +2° C. and add sodium tetrahydroborate (4.55 moles; 172.18 g) in portions over 3 hours maintaining the internal temperature between 0 and +5° C. during addition. When the addition is complete, stir the mixture at 5° C. for 1 hour. Add further sodium tetrahydroborate (687.24 mmoles; 26.00 g) and stir the mixture for 30 minutes. Add additional sodium tetrahydroborate (0.45 equiv; 687.24 mmoles; 26.00 g) and stir the mixture overnight. Pour the mixture into MTBE (5 L) and water (10 L). Slowly add hydrochloric acid (2 N) with stirring until mixture is slightly acidic to pH paper. Separate the organic layer, wash with brine, dry over MgSO4, filter, and concentrate under reduced pressure to afford the title compound in acceptable purity for use in the next step (1547 g; assumed 66% purity and 100% yield for the purposes of calculation in the next reaction) mass spectrum (m/z): 656.4 (M+1-18).

Provenance & Evidence