Sodium Carbonate → 5,6,7,8-Tetrahydro-6-(propyl(2-(2-thienyl)ethyl)amino)-1-naphthalenol

Participants

Reaction Steps

13.1 kg (63.9 mol) (−)-5-hydroxy-N-n-propyl-2-aminotetralin, 51.6 kg (182 mol) 2-(2-thienyl)ethanol toluenesulfonate, and 4.1 kg (38.6 mol) sodium carbonate (0.6 molar ratio Na2CO3/amine starting material) were mixed in a reactor under a nitrogen atmosphere using xylenes (150 kg) as a solvent with vigorous agitation and heated to a temperature of 120° C. to 125° C. for a period of 32 hours. HPLC analysis of the reaction mixture showed less than 2% of the starting material remaining, and the reaction was halted. The product, (−)-5-hydroxy-2-[N-n-propyl-N-2-(2-thienyl)ethylamino]tetralin, was isolated in the usual manner well known to those skilled in the art without chromatographic purification to yield product that was converted to its hydrochloride salt form, with a yield of 13.2 kg (59%).

Provenance & Evidence