反应详情

1N NaOH solution (40 ml) was added to a suspension of 6-amino-5,6,7,8-tetrahydronaphthalene-2-carboxylic acid (15.0 g, 79.0 mmol, 1.0 eq.) in dioxane-water (4:1, 100 ml) and then (Boc)2O (25.83 ml, 118.5 mmol, 1.5 eq.) was added dropwise to the reaction mixture at 0° C. and it was stirred at RT for 4 h. Dioxane was evaporated under reduced pressure and the residual aqueous layer was diluted with water (200 ml) and acidified with KHSO4 solution. The solid product was collected by filtration and dried to yield the desired compound as a white solid. Yield: 96% (22.0 g, 75.6 mmol) 2. To a suspension of 6-(tert-butoxycarbonylamino)-5,6,7,8-tetrahydronaphthalene-2-carboxylic acid (18.0 g, 61.86 mmol, 1.0 eq.) in THF (200 ml) was added HATU (23.5 g, 61.86 mmol, 1.0 eq.) and DIPEA (30.62 ml, 185.6 mmol, 3.0 eq.) at 0° C. and the reaction mixture was allowed to stir for 15 min. Piperidine (18.3 ml, 185.6 mmol, 3.0 eq.) was added dropwise to the reaction mixture at 0° C. and the resulting mixture was stirred at RT for 16 h. The reaction mixture was diluted with ethyl acetate (300 ml), washed with sat. NaHCO3 solution (200 ml), sat. NH4Cl solution (200 ml), water (200 ml) and brine (200 ml), and dried over Na2SO4. The solvent was evaporated under reduced pressure to obtain the crude material which was purified by column chromatography (silica gel; 1-3% MeOH/DCM) to yield the desired product as a brownish sticky solid. Yield: 90% (19.93 g, 55.67 mmol) 3. TFA (25 ml) was added to a cooled (0° C.) solution of tert-butyl 6-(piperidine-1-carbonyl)-1,2,3,4-tetrahydronaphthalen-2-ylcarbamate (8.33 g, 23.26 mmol, 1.0 eq.) in DCM (25 ml) and the reaction mixture was stirred at RT for 4 h. After completion of the reaction (monitored by TLC) the solvent was evaporated under reduced pressure. The residue was dissolved in MeOH (225 ml), basified with Amberlyst (A-21) ion exchange resin up to pH≈9-10 and filtered. The filtrate was concentrated to dryness to obtain the desired product as a light yellow solid which was employed in the next step. 4. (6-Amino-5,6,7,8-tetrahydronaphthalen-2-yl)(piperidin-1-yl)methanone (23.26 mmol, 1.0 eq.) was added portionwise to a stirred suspension of LAH (4.42 g, 116.3 mmol, 5.0 eq.) in dry THF (60 ml) under a N2 atmosphere at 0° C. and the resulting reaction mixture was stirred at RT for 16 h. The reaction mixture was quenched with a THF-water mixture (9:1, 60 ml) and the diluted with THF (300 ml). 10% NaOH solution (12 ml) was added to the mixture at −10° C. and it was stirred at RT for 2 h. The reaction mixture was filtered through celite and the filtrate was evaporated to dryness to yield the desired product as a light brown sticky oil. Yield: 90% (5.10 g, 20.9 mmol) 5. (Boc)2O (6.54 ml, 30.0 mmol, 1.5 eq.) was added dropwise to a mixture of 6-(piperidin-1-ylmethyl)-1,2,3,4-tetrahydronaphthalen-2-amine (4.88 g, 20.0 mmol, 1.0 eq.) and TEA (5.55 ml, 40.0 mmol, 2.0 eq.) in DCM (50 ml) at 0° C. and the resulting reaction mixture was stirred at RT for 14 h. The reaction mixture was diluted with DCM (50 ml), washed with sat. NH4Cl solution (2×50 ml) and brine (50 ml), and dried over Na2SO4. The solvent was evaporated under reduced pressure to yield the crude product which was purified by column chromatography (silica gel; 2% MeOH/DCM) to obtain the desired product as an off white solid. Yield: 80% (5.5 g, 15.98 mmol) 6. A solution of tert-butyl 6-(piperidin-1-ylmethyl)-1,2,3,4-tetrahydronaphthalen-2-ylcarbamate (500 mg, 1.45 mmol, 1.0 eq.) in THF (5 ml) was added dropwise to a stirred suspension of LAH (552 mg, 14.5 mmol, 10.0 eq.) in THF (10 ml) at 0° C. After complete addition, the reaction mixture was warmed to RT and stirred for 10 min. Then the reaction mixture was heated at reflux for 2 h. The reaction mixture was cooled to RT and quenched with THF-water (9:1, 4.5 ml) and then 20% NaOH solution was added at 0° C. The reaction mixture was diluted with THF (50 ml) and stirred at RT for 1 h. The mixture was then filtered through celite and the filtrate was concentrated to dryness to yield desired product which was employed in the next step without further purification. Yield: 85% (320 mg, 1.24 mmol)

1. customAfter completion of the reaction (monitored by TLC) the solvent
2. customwas evaporated under reduced pressure
3. dissolutionThe residue was dissolved in MeOH (225 ml)
4. filtrationfiltered
5. concentrationThe filtrate was concentrated to dryness