1,2,3,4-Tetrahydro-N-methyl-2-naphthalenamine hydrochloride synthesis

Yield:22583-90-0 1.66 g

Reaction Conditions:

Stage #1: tert-butyl 1,2,3,4-tetrahydroisoquinoline-2-carboxylatewith lithium aluminium tetrahydride in tetrahydrofuran; for 3 h;Reflux;
Stage #2: with hydrogenchloride in 1,4-dioxane;diethyl ether at 20;

Steps:

45 5.1.45. N-Methylindan-2-amine hydrochloride (12e)27

General procedure: 2-Aminoindane (19) (3.10 g, 23.3 mmol) was dissolved in CH₂Cl₂ (50 mL), Boc₂O (5.20 g, 23.8 mmol) and TEA (5 mL) were added under ice-cooling, and the mixture was stirred at room temperature for 2 h. The reaction mixture was diluted with a 1:1 EtOAc/hexane (100 mL) solution, and the organic layer was washed with 10% aqueous citric acid solution, saturated aqueous NaHCO₃ and brine and dried over MgSO₄. The insoluble material was filtered off, and the solution was concentrated under reduced pressure to give 4.68 g of 20a as a colorless oil. This was added to a suspension of LiAlH₄ (2.56 g, 67.5 mmol) in THF (100 mL), and the mixture was heated under reflux conditions for 3 h. The reaction mixture was ice-cooled, and H₂O (2.56 mL), 15% aqueous NaOH (2.56 mL), H₂O (7.68 mL) and MgSO₄ were successively added with stirring. The insoluble material was filtered off through Celite, nd the solution was concentrated under reduced pressure to give an oil (3.15 g). This was dissolved in diethyl ether (50 mL), 4 mol/L HCl in dioxane (6 mL) was added, and the precipitated solid was filtered, washed with diethyl ether and dried under reduced pressure to give 12e (3.53 g, 83%) as a colorless solid.

References:

Nakao, Akira;Suzuki, Hiroko;Ueno, Hiroaki;Iwasaki, Hiroshi;Setsuta, Tomofumi;Kashima, Akiko;Sunada, Shinji [Bioorganic and Medicinal Chemistry,2015,vol. 23,# 15,p. 4952 - 4969]