Acetonitrile → p-Toluenesulfonic acid

Participants

Reaction Steps

The filtrate from step (ii) that contains (5) dissolved in isopropyl acetate and acetonitrile is diluted with 5.5 L of 200 proof ethanol. While stirring, p-toluene sulfonic acid hydrate (1.04 kg, 5.49 mol) in 3.3 L of 200 proof ethanol is added dropwise over 30 minutes. An off white solid crystallizes from the reaction mixture. After stirring 16 hours the solid is collected by filtration, washed twice with 7.5 L portions of isopropyl acetate, and once with 3.5 L of 200 proof ethanol. The solid is dried in a vacuum oven to yield 2.38 kg of p-toluene sulfonic acid salt of 5-amino-3-(2′-O-acetyl-3′-deoxy-beta-D-ribofuranosyl)-3H-thiazolo[4,5]pyrimidine-2-one with >98% purity by HPLC.

Provenance & Evidence