Sulfuric Acid → HCID 5274983, compound

Participants

Reaction Steps

Two hundred mg of 6-cyanobenzothieno[3,2-h]isoquinoline (4), prepared in the preceding Example, was mixed with a solution of 2 ml water and 3 ml concentrated sulfuric acid. The reaction mixture was heated at 110° C.-120° C., and gave rise to a yellowish brown solution. After heating for approximately 5 hr, when TLC indicated the absence of starting material, the reaction mixture was poured onto 40 ml ice and water. The yellow solution thus obtained was made alkaline (to a pH of about 8) with concentrated ammonium hydroxide. The gray flocculent solid that precipitated was collected and washed with water to yield 130 mg dried product. This material was recrystallized from 75 ml CHCl3, to give 85 mg of a white solid, m.p. 295° C.-302° C., characterized as compound 5 by I.R. and mass spectrometry.

Provenance & Evidence