p-Toluenesulfonic acid → HCID 57824504, compound

Participants

Reaction Steps

A solution of (2R,3R,4R,5S,6S)-5-benzyloxy-3,4-dimethoxy-6-methyl-tetrahydropyran-2-ol (prepared according to Wu et al., Carbohydr. Res. 1998, 306, 493; 10.5 g, 26.6 mmol), N-hydroxysuccinimide (5.0 g, 50 mmol) and TsOH (250 mg, cat.) in benzene (100 mL) was heated at reflux for 24 h with removal of H2O using a Dean-Stark trap. The brown solution was cooled, filtered, washed with saturated NaHCO3 solution and concentrated. The gummy oil was purified by silica gel chromatography, eluting with 70:30 hexanes-acetone. The pure O-succinimide (7.5 g, 14.5 mmol) was then transferred to a 500-mL Parr hydrogenation apparatus and debenzylated using Pd(OH)2/C (0.95 g) in EtOH (75 mL). The solution, which took up 19 pounds per square inch (psi) of hydrogen over 24 h, was then filtered and concentrated, leaving a solid residue which was recrystallized from EtOH to give a white solid (3.25 g).

Provenance & Evidence