Naphthalene → 1,3,6-Naphthalenetrisulfonic acid

Participants

Reaction Steps

Naphthalene is introduced at 30° to 35° C. into monohydrate (=100% strength H2SO4), 65% strength oleum being run in at the same time. The reaction mixture is kept at 50° C. for one hour, at 70° C. for one hour and at 90° C. for seven hours, until everything has dissolved. With this process the yield of naphthalene-1,3,5-trisulphonic acid is about 68%, based on the naphthalene employed. In addition, about 21% of naphthalene-1,3,6-trisulphonic acid and about 4 to 5% of naphthalene-1,3,7-trisulphonic acid are formed (see Example 6).

Provenance & Evidence