Potassium Carbonate → Tert-butyl 4-[4-[6-amino-5-(1,3-benzoxazol-2-yl)-3-pyridyl]-3-formyl-pyrazol-1-yl]piperidine-1-carboxylate

HRID 908398Notes

Reaction equation

HRID 908398 reaction equation
[O:1]1[C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][C:4]=2[N:3]=[C:2]1[C:10]1[C:11]([NH2:25])=[N:12][CH:13]=[C:14](B2OC(C)(C)C(C)(C)O2)[CH:15]=1.Br[C:27]1[C:28]([CH:45]=[O:46])=[N:29][N:30]([CH:32]2[CH2:37][CH2:36][N:35]([C:38]([O:40][C:41]([CH3:44])([CH3:43])[CH3:42])=[O:39])[CH2:34][CH2:33]2)[CH:31]=1.C(=O)([O-])[O-].[K+].[K+]>C(#N)C.[Pd].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>[NH2:25][C:11]1[N:12]=[CH:13][C:14]([C:27]2[C:28]([CH:45]=[O:46])=[N:29][N:30]([CH:32]3[CH2:33][CH2:34][N:35]([C:38]([O:40][C:41]([CH3:42])([CH3:44])[CH3:43])=[O:39])[CH2:36][CH2:37]3)[CH:31]=2)=[CH:15][C:10]=1[C:2]1[O:1][C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][C:4]=2[N:3]=1

Participants

6

Reactant 3

HCID 11430Potassium CarbonateHCID 673889123-(1,3-Benzoxazol-2-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2-amineHCID 86630149Tert-butyl 4-(4-bromo-3-formyl-pyrazol-1-yl)piperidine-1-carboxylate

Product 1

HCID 86630148Tert-butyl 4-[4-[6-amino-5-(1,3-benzoxazol-2-yl)-3-pyridyl]-3-formyl-pyrazol-1-yl]piperidine-1-carboxylateYield 85.1%

Reagents, catalysts & solvents 2

HCID 11979704Tetrakis(triphenylphosphine)palladiumCatalystHCID 6342AcetonitrileSolvent

Procedure

A suspension of 3-(1,3-benzoxazol-2-yl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2-amine (0.3 g), tert-butyl 4-(4-bromo-3-formyl-pyrazol-1-yl)piperidine-1-carboxylate (0.362 g), potassium carbonate (0.335 g) and tetrakis(triphenylphosphine) palladium (0.093 g) in degassed acetonitrile (50 mL) was stirred at reflux overnight. The resulting suspension was cooled to ambient temperature, filtered, washed with dichloromethane (3×20 ml) and the filtrate was concentrated. The crude product was purified by flash chromatography on silica gel eluting with 5 to 90% ethyl acetate in petroleum ether. The solvent was evaporated to dryness to afford tert-butyl 4-[4-[6-amino-5-(1,3-benzoxazol-2-yl)-3-pyridyl]-3-formyl-pyrazol-1-yl]piperidine-1-carboxylate (0.370 g) as a solid. NMR Spectrum: (DMSOd6) 1.44 (s, 9H), 1.87 (dd, 1H), 1.92 (dd, 1H), 2.09-2.18 (m, 2H), 2.97 (bs, 2H), 4.04-4.16 (m, 2H), 4.52-4.61 (m, 1H), 7.41-7.49 (m, 2H), 7.80 (dd, 1H), 7.82 (bs, 2H), 7.85 (dd, 1H), 8.48 (s, 1H), 8.56 (d, 1H), 8.65 (d, 1H), 9.99 (s, 1H); Mass spectrum: M+H+ 489.

Workup

  1. temperatureat reflux overnight
  2. filtrationfiltered
  3. washwashed with dichloromethane (3×20 ml)
  4. concentrationthe filtrate was concentrated
  5. customThe crude product was purified by flash chromatography on silica gel eluting with 5 to 90% ethyl acetate in petroleum ether
  6. customThe solvent was evaporated to dryness

Sources & evidence

ORD record
ord-b311ff4ab8524600adb17b9107eca4db
Source dataset
uspto-grants-2011_09
Patent number
US08017611B2

Reaction notes

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