Trifluoroacetic acid → 2-Amino-3-(7,7-dimethyl-1,4,6,7-tetrahydro-pyrazolo[4,3-c]pyridin-5-yl)-propionic acid methyl ester

HRID 1177735Notes

Reaction equation

HRID 1177735 reaction equation
[CH3:1][O:2][C:3](=[O:32])[CH:4]([N:17](C(OC(C)(C)C)=O)C(OC(C)(C)C)=O)[CH2:5][N:6]1[CH2:11][C:10]([CH3:13])([CH3:12])[C:9]2[NH:14][N:15]=[CH:16][C:8]=2[CH2:7]1.FC(F)(F)C(O)=O>C(Cl)Cl>[CH3:1][O:2][C:3](=[O:32])[CH:4]([NH2:17])[CH2:5][N:6]1[CH2:11][C:10]([CH3:13])([CH3:12])[C:9]2[NH:14][N:15]=[CH:16][C:8]=2[CH2:7]1

Participants

4

Reactant 2

HCID 6422Trifluoroacetic acidHCID 588644042-(Di-tert-butoxycarbonylamino)-3-(7,7-dimethyl-1,4,6,7-tetrahydro-pyrazolo[4,3-c]pyridin-5-yl)-propionic acid methyl ester

Product 1

HCID 588644942-Amino-3-(7,7-dimethyl-1,4,6,7-tetrahydro-pyrazolo[4,3-c]pyridin-5-yl)-propionic acid methyl esterYield 94%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a solution of 2-(di-tert-butoxycarbonylamino)-3-(7,7-dimethyl-1,4,6,7-tetrahydro-pyrazolo[4,3-c]pyridin-5-yl)-propionic acid methyl ester (0.49 g, 1 equiv) in methylene chloride (5 mL, 0° C.) was added trifluoroacetic acid (1.5 mL). The ice bath was removed and stirring continued for 2 h. The solution was concentrated, redissolved in methanol, and loaded onto a column of strong cation exchange resin. After flushing with methanol, the product was removed from the column by eluting with 2M ammonia in methanol to afford the product as its free base (250 mg, 94%). 1H-NMR (CDCl3, 500 MHz) δ 1.27 (s, 3H), 1.28 (s, 3H), 2.41 (d, J=11.3, 1H), 2.50 (d, J=11.3, 1H), 2.69 (dd, J=12.5, 7.9, 1H), 2.82 (dd, J=12.5, 5.2, 1H), 3.45 (d, J=12.8, 1H), 3.52 (d, J=12.8, 1H), 3.67 (m, 1H), 3.69 (s, 3H), 7.19 (s, 1H). Mass spec.: 253.16 (MH)+.

Workup

  1. customThe ice bath was removed
  2. concentrationThe solution was concentrated
  3. dissolutionredissolved in methanol
  4. customAfter flushing with methanol
  5. customthe product was removed from the column
  6. washby eluting with 2M ammonia in methanol

Sources & evidence

ORD record
ord-74e28c910c1143b4b23723079303ba35
Source dataset
uspto-grants-2010_11
Patent number
US07842808B2

Reaction notes

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