Sulfuric Acid → (S)-3-hydroxysulphonyloxymethyl1,2,3,4-tetrahydroisoquinoline

Participants

Reaction Conditions

Reaction Steps

A solution of (S)-3-hydroxymethyl-1,2,3,4-tetrahydroisoquinoline (41 g) in a mixture of sulphuric acid (d = 1.83; 13 cc) and water (70 cc) is heated at 110° C. Water (50 cc) is distilled off and the mixture is then concentrated under reduced pressure (20 mm Hg) at 100° C. The brown oily residue is taken up in a mixture of sulphuric acid (d = 1.83; 13 cc) and water (70 cc). Water (50 cc) is again distilled off and the mixture is then concentrated as previously described, after which the concentration is finished at 100° C under reduced pressure (1 mm Hg). The residue which crystallises on cooling, is redissolved in a hot mixture of ethanol (140 cc) and water (60 cc). After cooling for 15 hours at about 5° C the resulting crystals are filtered off and washed with a mixture (20 cc) of ethanol and water (3:1 by volume) and then with ethanol (2 × 25 cc). After drying at 60° C under reduced pressure (1 mm Hg), (S)-3-hydroxysulphonyloxymethyl-1,2,3,4-tetrahydroisoquinoline (48 g) is obtained in the form of white crystals.

Provenance & Evidence