Sulfuric Acid → HCID 70403118, compound

Participants

Reaction Steps

In 900 g of toluene, 600 g of the same crude isoquinoline as used in the refining process of No. 1 above was dissolved. To the resultant solution, sulfuric acid in amounts equimolar with the isoquinoline was added to react thereon. The crystals consequently formed were separated by filtration to afford crystals of isoquinolinium sulfate. The crystals were washed with 900 g of toluene and then decomposed with an alkali by following the procedure of No. 1. Consequently, there was obtained 450 g of isoquinoline having a total sulfur content of 300 ppm. Then, the aforementioned isoquinoline and 22.5 g of Raney nickel added thereto were treated at 100° C. in an atmosphere of nitrogen for 1 hour. The resultant reaction mixture was subjected to solid-liquid separation and to simple distillation to afford 420 g of refined isoquinoline having a total sulfur contet of less than 1 ppm.

Provenance & Evidence