Ammonia → 6-Methoxy-1,2,3,4-tetrahydro-1-naphthalenylamine

HRID 1910603Notes

Reaction equation

HRID 1910603 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]2[C:10](=[CH:11][C:12]=1OC)[C:9](=O)[CH2:8][CH2:7][CH2:6]2.[NH3:16].C(O)C.[BH4-].[Na+]>CC(C)[O-].[Ti+4].CC(C)[O-].CC(C)[O-].CC(C)[O-]>[CH3:1][O:2][C:3]1[CH:4]=[C:5]2[C:10](=[CH:11][CH:12]=1)[CH:9]([NH2:16])[CH2:8][CH2:7][CH2:6]2

Participants

6

Reactant 4

HCID 222AmmoniaHCID 702EthanolHCID 2668163,4-Dihydro-6,7-dimethoxy-1(2H)-naphthalenoneHCID 4311764Sodium borohydride

Product 1

HCID 382506-Methoxy-1,2,3,4-tetrahydro-1-naphthalenylamineYield 24%

Reagents, catalysts & solvents 1

HCID 11026Titanium isopropoxideCatalyst

Conditions

Temperature
0 °C

Procedure

3,4-Dihydro-6,7-dimethoxynaphthalen-1(2H)-one (25.0 mmol), titanium(IV) isopropoxide (50.0 mmol) and 2 M solution of ammonia in ethanol (120 mmol) were stirred at room temperature for 6 h. The reaction was cooled to 0° C. and sodium borohydride was added portionwise during 10 min (40.0 mmol); the resultant mixture was stirred at rt for an additional 3 h. The reaction was quenched by pouring it into ammonium hydroxide (2 M, 130 mL), the precipitate that formed was filtered off and washed with ethyl acetate (25 mL×3). The organic layer was separated and the remaining aqueous layer was extracted with ethyl acetate (25 mL×2). The combined organic extracts were washed with 1 M HCl (50 mL). The acidic aqueous extracts were washed with ethyl acetate (100 mL), then treated with aqueous sodium hydroxide (2 M) to pH 10-12, and extracted with ethyl acetate (75 mL×3). The combined organic extracts were washed with brine (75 mL), dried (Na2SO4), and concentrated in vacuo to afford the desired product (24% yield). 1H NMR (400 MHz, CDCl3): δ 7.31 (d, 1H), 6.74 (dd, 1H), 6.60 (d, 1H), 3.94 (m, 1H), 3.78 (s, 3H), 2.75 (m, 2H), 2.01 (m, 2H), 1.72 (m, 2H).

Workup

  1. customThe reaction was quenched
  2. additionby pouring it into ammonium hydroxide (2 M, 130 mL)
  3. customthe precipitate that formed
  4. filtrationwas filtered off
  5. washwashed with ethyl acetate (25 mL×3)
  6. customThe organic layer was separated
  7. extractionthe remaining aqueous layer was extracted with ethyl acetate (25 mL×2)
  8. washThe combined organic extracts were washed with 1 M HCl (50 mL)
  9. washThe acidic aqueous extracts were washed with ethyl acetate (100 mL)
  10. additiontreated with aqueous sodium hydroxide (2 M) to pH 10-12
  11. extractionextracted with ethyl acetate (75 mL×3)
  12. washThe combined organic extracts were washed with brine (75 mL)
  13. dry with materialdried (Na2SO4)
  14. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-bf4bd0b8104b4eefb6563eaa9a8f6267
Source dataset
uspto-grants-2013_12
Patent number
US08604021B2

Reaction notes

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