Phosphorus oxychloride → HCID 19819790, compound

Participants

Reaction Steps

A mixture of 2-hydroxybenzimidazole (200 g) and phosphorus oxychloride (1100 ml) was heated at reflux temperature for 1 hr and HCl gas was bubbled into the mixture for 3.5 hr. The excess phosphorus oxychloride was removed on a rotary evaporator. The residual oil was poured into ice water (2 L) and a solid impurity was removed by filtration. The filtrate was basified to pH 8 with concentrated ammonium hydroxide. The solid product was collected and dried at 60° C. in vacuo for 18 hrs. The product was recrystallized from acetone to obtain 70 g of the title compound.

Provenance & Evidence