p-Toluenesulfonic acid → HCID 12110021, compound

Participants

Reaction Steps

p-Toluenesulfonic acid (0.8 g) was added to a suspension of Compound 45a (1.0 g) obtained in Step A of Example 45 in toluene (27 ml), followed by heating under reflux for 30 minutes. After being allowed to stand for cooling, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution for neutralization, followed by extraction with ether. The organic layer was washed with a saturated saline and dried over anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure. The resultant residue was purified by silica gel column chromatography (chloroform/methanol=20/1) to give Compound 67 (0.59 g, 62.2%) as yellow crystals.

Provenance & Evidence