Sodium Bicarbonate → HCID 67238887, compound

Participants

Reaction Steps

10 g of (S)-(−)-2-(N-propylamino)-5-hydroxytetraline, S-(III), obtained according to Example 2 were mixed with 9 g of NaHCO3 (2.2 equivalents) and 16 g of 2-(2-thienyl)ethanol 2-nitrobenzenesulfonate (1.05 equivalents) in 80 mL of acetonitrile. The mixture was refluxed for 9 hours, and then cooled and filtered for removal of suspended salts. 60 mL of water were added to the filtrate and concentrated by distillation for removal of acetonitrile. 40 mL of toluene were added and the layers were separated. The organic layer was twice washed with 10% NaHCO3. Then, 50 mL of water and H3PO4 were added to pH=1-2. After layer separation, the aqueous acid layer was neutralized with 30% K2CO3 to pH=7-7.5 and extracted with 20 mL of ethyl acetate. The organic layer was washed with 10 mL of water, concentrated by distillation from the solvent to provide 10 g of (6S)-(−)-5,6,7,8-tetrahydro-6-[propyl-(2-thienyl)ethyl]amino-1-naphthol, S-(I), as a white solid (70% yield).

Provenance & Evidence