Acetic Acid → (1S,2R,3S,4R)-3-(4-fluorobenzylamino)-bicyclo[2.2.1]heptane-2-carboxylic acid ethyl ester

HRID 2408776Notes

Reaction equation

HRID 2408776 reaction equation
[CH2:1]([O:3][C:4]([C@H:6]1[C@@H:11]([NH2:12])[C@H:10]2[CH2:13][C@@H:7]1[CH2:8][CH2:9]2)=[O:5])[CH3:2].[F:14][C:15]1[CH:22]=[CH:21][C:18]([CH:19]=O)=[CH:17][CH:16]=1.C(O)(=O)C.C([BH3-])#N.[Na+]>C(O)C.C(OCC)(=O)C>[CH2:1]([O:3][C:4]([C@H:6]1[C@@H:11]([NH:12][CH2:19][C:18]2[CH:21]=[CH:22][C:15]([F:14])=[CH:16][CH:17]=2)[C@H:10]2[CH2:13][C@@H:7]1[CH2:8][CH2:9]2)=[O:5])[CH3:2]

Participants

7

Procedure

To a solution of (1S,2R,3S,4R)-3-amino-bicyclo[2.2.1]heptane-2-carboxylic acid ethyl ester (1.15 g, 6.28 mmol) in ethanol (30 mL) was added 4-fluorobenzaldehyde (0.68 mL, 6.31 mmol), glacial acetic acid (0.4 mL, 6.99 mmol), and sodium cyanoborohydride (1.04 g, 15.7 mmol) at 25° C. After stirring for 3 h, the mixture was diluted with ethyl acetate (50 mL) and quenched with saturated aqueous sodium bicarbonate (50 mL) for 0.5 h. The mixture was filtered through Celite. The organic layer was separated and the aqueous layer was extracted with ethyl acetate (50 mL×2). When all solvent was removed, a solid was formed. The solid was filtered, washed with water, and dried under vacuum to afford (1S,2R,3S,4R)-3-(4-fluorobenzylamino)-bicyclo[2.2.1]heptane-2-carboxylic acid ethyl ester (1.74 g, 5.97 mmol, 95% yield) as a white solid. 1H NMR (400 MHz, CDCl3) δ: 1.05-1.16 (2H, m), 1.21 (1H, dt, J1=8.0 Hz, J2=1.6 Hz), 1.27 (3H, t, J=7.4 Hz), 1.45-1.61 (2H, m), 1.94 (1H, dt, J1=10.1 Hz, J2=1.9 Hz), 2.28 (1H, d, J=3.9 Hz), 2.43 (1H, d, J=3.3 Hz), 2.60 (1H, dd, J1=8.8 Hz, J2=1.5 Hz), 2.94 (1H, d, J=7.8 Hz), 3.66 (1H, d, J=13.2 Hz), 3.80 (1H, d, J=13.5 Hz), 4.13 (2H, q, J=7.0 Hz), 6.97 (2H, t, J=8.5 Hz), 7.26 (2H, t, J=7.1 Hz).

Workup

  1. customquenched with saturated aqueous sodium bicarbonate (50 mL) for 0.5 h
  2. filtrationThe mixture was filtered through Celite
  3. customThe organic layer was separated
  4. extractionthe aqueous layer was extracted with ethyl acetate (50 mL×2)
  5. customWhen all solvent was removed
  6. customa solid was formed
  7. filtrationThe solid was filtered
  8. washwashed with water
  9. customdried under vacuum

Sources & evidence

ORD record
ord-b8d417236c1e4a20a13a14116b1b8281
Source dataset
uspto-grants-2014_08
Patent number
US08815847B2

Reaction notes

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