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

HRID 424235Notes

Reaction equation

HRID 424235 reaction equation
[C:1]1(=O)[CH2:5][CH2:4][CH2:3][CH2:2]1.[CH2:7]([O:9][C:10]([C@H:12]1[C@@H:17]([NH2:18])[C@H:16]2[CH2:19][C@@H:13]1[CH2:14][CH2:15]2)=[O:11])[CH3:8].C([BH3-])#N.[Na+].C(=O)(O)[O-].[Na+]>CO.C(O)(=O)C>[CH2:7]([O:9][C:10]([C@H:12]1[C@@H:17]([NH:18][CH:1]2[CH2:5][CH2:4][CH2:3][CH2:2]2)[C@H:16]2[CH2:19][C@@H:13]1[CH2:14][CH2:15]2)=[O:11])[CH3:8]

Participants

7

Reactant 4

HCID 8452CyclopentanoneHCID 516892Sodium BicarbonateHCID 5003444Sodium cyanoborohydrideHCID 13396165diexo-3-Amino-bicyclo[2.2.1]heptane-2-carboxylic acid ethyl ester

Product 1

HCID 66674565(1S,2R,3S,4R)-3-cyclopentylamino-bicyclo[2.2.1]heptane-2-carboxylic acid ethyl esterYield 75%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 887MethanolSolvent

Procedure

Cyclopentanone (0.12 mL, 1.38 mmol) was added to a solution of (1S,2R,3S,4R)-3-amino-bicyclo[2.2.1]heptane-2-carboxylic acid ethyl ester (prepared as described in Example 6k, 230 mg, 1.26 mmol) in anhydrous methanol (10 mL) at 25° C. under a nitrogen atmosphere. After stirring for 10 min, glacial acetic acid (0.5 mL) and sodium cyanoborohydride (260 mg, 3.15 mmol) were added sequentially, and the resulting mixture was stirred at 50° C. for 30 min. The reaction mixture was poured into saturated aqueous sodium bicarbonate solution and extracted with ethyl acetate. The combined organic layers were washed with saturated aqueous brine solution, dried over sodium sulfate and filtered. The filtrate was concentrated in vacuo to afford the desired product, (1S,2R,3S,4R)-3-cyclopentylamino-bicyclo[2.2.1]heptane-2-carboxylic acid ethyl ester (237 mg, 0.94 mmol, 75%), as a yellow oil. LC-MS (ESI) calcd for C15H25NO2 251.19, found 252.0 [M+H+].

Workup

  1. stirringthe resulting mixture was stirred at 50° C. for 30 min
  2. extractionextracted with ethyl acetate
  3. washThe combined organic layers were washed with saturated aqueous brine solution
  4. dry with materialdried over sodium sulfate
  5. filtrationfiltered
  6. concentrationThe filtrate was concentrated in vacuo

Sources & evidence

ORD record
ord-e64275550d9f415a8638d913af9e4aac
Source dataset
uspto-grants-2012_01
Patent number
US08101800B2

Reaction notes

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