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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of (S)-3-hydroxymethyl-1,2,3,4-tetrahydroisoquinoline (41 g) in a mixture of 34 N sulphuric acid (13 cc) and water (70 cc) is heated at 110° C. Water (about 50 cc) is distilled off and the residue is then concentrated at 100° C. under reduced pressure (20 mm Hg). The brown oily residue is taken up in a mixture of 34 N sulphuric acid (13 cc) and water (70 cc). Water (50 cc) is again distilled off, the mixture is then concentrated as described above, and the concentration process is concluded at 100° C. under reduced pressure (1 mm Hg). The residue, which crystallises on cooling, is recrystallised from a 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.

Herkunft & Nachweise