7-Nitro-1-tetralone → N-(5,6,7,8-Tetrahydronaphthalen-2-yl)acetamide

Temperature

20 °C

A solution of 7-nitro-3,4-dihydro-1(2H)-naphthalenone (1.67 g, 8.7 mmol) in EtOAc/EtOH (1:1, 150 mL), water (15 mL) and cHCl (2 mL) with Pd/C (5%, 500 mg) was stirred vigorously under H2 (60 psi) for 16 h. The suspension was filtered through Celite, washed with EtOH (4×10 mL) and the organic solvent evaporated. The aqueous residue was partitioned between DCM and dilute aqueous NH3 solution and the organic fraction dried and the solvent evaporated. The residue was dissolved in dioxane (20 mL), and AcO (1.8 mL, 19.2 mmol) was added dropwise to the solution at 0° C. The solution was stirred at 20° C. for 16 h, diluted with water (50 mL), and partitioned between EtOAc and dilute aqueous NH3 solution. The organic fraction was washed with water (3×20 mL), dried and the solvent evaporated to give N-(5,6,7,8-tetrahydro-2-naphthalenyl)acetamide 166 (1.57 g, 95%) as a white solid: 1H NMR δ 7.18-7.25 (m, 2H, H-1, NH), 7.15 (dd, J=8.2, 2.1 Hz, 1H, H-3), 7.00 (d, J=8.2 Hz, 1H, H-4), 2.69-2.77 (m, 4H, 2×CH2), 2.15 (s, 3H, CH3), 1.74-1.80 (m, 4H, 2×CH2). The procedure was repeated a number of times to give N-(5,6,7,8-tetrahydro-2-naphthalenyl)acetamide 166 (10.21 g, 88% overall).

1. filtrationThe suspension was filtered through Celite
2. washwashed with EtOH (4×10 mL)
3. customthe organic solvent evaporated
4. customThe aqueous residue was partitioned between DCM and dilute aqueous NH3 solution
5. customthe organic fraction dried
6. customthe solvent evaporated
7. dissolutionThe residue was dissolved in dioxane (20 mL)
8. additionAcO (1.8 mL, 19.2 mmol) was added dropwise to the solution at 0° C
9. custompartitioned between EtOAc and dilute aqueous NH3 solution
10. washThe organic fraction was washed with water (3×20 mL)
11. customdried
12. customthe solvent evaporated

ORD record

ord-49e6196817ca4a2cad87572cfba51bdf

Source dataset

uspto-grants-2011_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07989451B2