Sodium Carbonate → [5-(Tert-butyl-diphenyl-silanyloxymethyl)-2-methyl-pyrazolo[1,5-a]pyridin-3-yl]-oxo-acetic acid methyl ester

HRID 402874Notes

Reaction equation

HRID 402874 reaction equation
[CH3:1][O:2][C:3](=[O:7])[C:4](Cl)=[O:5].[C:8]([SiH2:12][O:13][C:14]([C:31]1[CH:36]=[CH:35][CH:34]=[CH:33][CH:32]=1)([C:25]1[CH:30]=[CH:29][CH:28]=[CH:27][CH:26]=1)[C:15]1[CH:20]=[CH:19][N:18]2[N:21]=[C:22]([CH3:24])[CH:23]=[C:17]2[CH:16]=1)([CH3:11])([CH3:10])[CH3:9].C(=O)([O-])[O-].[Na+].[Na+]>C1COCC1>[CH3:1][O:2][C:3](=[O:7])[C:4]([C:23]1[C:22]([CH3:24])=[N:21][N:18]2[CH:19]=[CH:20][C:15]([C:14]([C:31]3[CH:32]=[CH:33][CH:34]=[CH:35][CH:36]=3)([C:25]3[CH:26]=[CH:27][CH:28]=[CH:29][CH:30]=3)[O:13][SiH2:12][C:8]([CH3:11])([CH3:10])[CH3:9])=[CH:16][C:17]=12)=[O:5]

Participants

5

Reactant 3

HCID 10340Sodium CarbonateHCID 79846Methyl chloroglyoxylateHCID 1317297495-(Tert-butyl-diphenyl-silanyloxymethyl)-2-methyl-pyrazolo[1,5-a]pyridine

Product 1

HCID 131729748[5-(Tert-butyl-diphenyl-silanyloxymethyl)-2-methyl-pyrazolo[1,5-a]pyridin-3-yl]-oxo-acetic acid methyl esterYield 92%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
120 °C

Procedure

In a reaction tube, chloro-oxo-acetic acid methyl ester (2.47 ml, 26.0 mmol, 4.0 equiv) is added to a solution of 5-(tert-butyl-diphenyl-silanyloxymethyl)-2-methyl-pyrazolo[1,5-a]pyridine (2.6 g, 6.49 mmol) in THF (20 ml) under an atmosphere of argon. The tube is sealed under argon, and the reaction mixture is heated under microwave irradiation for 15 minutes at 120° C. After cooling, the reaction mixture is carefully poured into an aqueous solution of sodium carbonate. After three extractions with EtOAc, the combined organic layers are dried over Na2SO4, filtered and concentrated in vacuo. Purification via flash chromatography (hexane/EtOAc 4:1) affords the title compound (2.9 g, 92%). 1H NMR (400 MHz, d6-DMSO): δ=8.76 (d, J=7.8 Hz, 1H), 8.11 (br s, 1H), 7.61-7.59 (m, 4 H), 7.44-7.35 (m, 6H), 7.10 (dd, J=7.1/1.9 Hz, 1H), 4.88 (s, 2H), 3.82 (s, 3H), 2.41 (s, 3H), 1.03 (s, 9H). MS (ES+): 487 (M+H)+.

Workup

  1. customThe tube is sealed under argon
  2. temperatureAfter cooling
  3. extractionAfter three extractions with EtOAc
  4. dry with materialthe combined organic layers are dried over Na2SO4
  5. filtrationfiltered
  6. concentrationconcentrated in vacuo
  7. customPurification via flash chromatography (hexane/EtOAc 4:1)

Sources & evidence

ORD record
ord-d04faf8f5bf848bb8d90c14f0525ddd1
Source dataset
uspto-grants-2014_06
Patent number
US08742132B2

Reaction notes

Loading…