Phosphate → HCID 14567294, compound

Participants

Reaction Steps

53.5 g 3-Chloro-1-phenyl-isoquinoline-4-aldehyde are suspended in 1.5 l of acetone and 500 ml of phosphate buffer of pH 7. At 40° C., 40 g of potassium permanganate are introduced portionwise within 2 hours and stirring is continued at this temperature for 2 hours. The excess potassium permanganate is destroyed with 10 g sodium hydrogenosulfite and the solution is concentrated to 500 ml and filtered. The filtrate is brought to pH 4 with concentrated hydrochloric acid followed by thorough extraction with acetic ester. Removal of the solvent in vacuo provides 41.1 g of 3-chloro-1-phenyl-isoquinoline-4 carboxylic acid having a melting point of 208° C.

Provenance & Evidence