Reaktion #527674

Reaktionsgleichung

hydrochloric acid

formaldehyde

sodium cyanoborohydride

hydrobromic acid

7-benzyloxy-1-[1-(2-chlorophenyl)cyclobutyl]-6-methoxy-1,2,3,4-tetrahydroisoquinoline

→

1-[1-(2-chlorophenyl)cyclobutyl]-7-hydroxy-6-methoxy-2-methyl-1,2,3,4-tetrahydroisoquinoline hydrobromide

Lösungsmittel

methanol

methanol

propan-2-ol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeprepared in a similar manner to that
2. 2
   Sonstigethe solvents removed by evaporation
3. 3
   SonstigeThe residue was partitioned between ethyl acetate and dilute aqueous sodium hydroxide solution
4. 4
   SonstigeThe organic layer yielded a gum which
5. 5
   Temperaturunder reflux for 1 hour
6. 6
   SonstigeThe solvents were removed by evaporation
7. 7
   Sonstigethe residue partitioned between ether and saturated aqueous sodium bicarbonate solution
8. 8
   SonstigeThe ether layer yielded a residue which
9. 9
   SonstigeThe solvent was removed by evaporation
10. 10
    Sonstigethe residue crystallised
11. 11
    Sonstigerecrystallised from propan-2-ol

Vorschrift

A mixture of the hydrochloride salt of 7-benzyloxy-1-[1-(2-chlorophenyl)cyclobutyl]-6-methoxy-1,2,3,4-tetrahydroisoquinoline (2.75 g prepared in a similar manner to that described in Example RB25), methanol (50 ml) and 37-40% aqueous formaldehyde solution (3 ml) was cooled to 10° C. and sodium cyanoborohydride (1.52 g) was added. The mixture was stirred for 24 hours and the solvents removed by evaporation. The residue was partitioned between ethyl acetate and dilute aqueous sodium hydroxide solution. The organic layer yielded a gum which was dissolved in methanol (25 ml) and concentrated hydrochloric acid (25 ml) and heated under reflux for 1 hour. The solvents were removed by evaporation and the residue partitioned between ether and saturated aqueous sodium bicarbonate solution. The ether layer yielded a residue which was dissolved in propan-2-ol (100 ml) and 48% aqueous hydrobromic acid (5 ml). The solvent was removed by evaporation and the residue crystallised and then recrystallised from propan-2-ol to give 1-[1-(2-chlorophenyl)cyclobutyl]-7-hydroxy-6-methoxy-2-methyl-1,2,3,4-tetrahydroisoquinoline hydrobromide, m.p. 148°-150° C.

Quelle