Citric Acid → (2S)-Methyl 3-(2-(tert-butyldiphenylsilyloxy)ethoxy)-2-(1-(2,3-dichlorophenyl)-1H-pyrazolo[3,4-d]pyrimidin-4-yloxy)propanoate

HRID 1098233Notes

Reaction equation

HRID 1098233 reaction equation
[H-].[Na+].[Si:3]([O:20][CH2:21][CH2:22][O:23][CH2:24][C@H:25]([OH:30])[C:26]([O:28][CH3:29])=[O:27])([C:16]([CH3:19])([CH3:18])[CH3:17])([C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1)[C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1.Cl[C:32]1[N:37]=[CH:36][N:35]=[C:34]2[N:38]([C:41]3[CH:46]=[CH:45][CH:44]=[C:43]([Cl:47])[C:42]=3[Cl:48])[N:39]=[CH:40][C:33]=12.C(O)(=O)CC(CC(O)=O)(C(O)=O)O.C(OC)(=O)C1OC1>C1COCC1>[Si:3]([O:20][CH2:21][CH2:22][O:23][CH2:24][C@H:25]([O:30][C:32]1[N:37]=[CH:36][N:35]=[C:34]2[N:38]([C:41]3[CH:46]=[CH:45][CH:44]=[C:43]([Cl:47])[C:42]=3[Cl:48])[N:39]=[CH:40][C:33]=12)[C:26]([O:28][CH3:29])=[O:27])([C:16]([CH3:19])([CH3:18])[CH3:17])([C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1)[C:4]1[CH:5]=[CH:6][CH:7]=[CH:8][CH:9]=1

Participants

7

Reactant 5

HCID 311Citric AcidHCID 24758Sodium hydrideHCID 145751Methyl oxirane-2-carboxylateHCID 574386164-chloro-1-(2,3-dichlorophenyl)-1H-pyrazolo[3,4-d]pyrimidineHCID 59279512(S)-methyl 3-(2-(tert-butyldiphenylsilyloxy)ethoxy)-2-hydroxypropanoate

Product 1

HCID 59279524(2S)-Methyl 3-(2-(tert-butyldiphenylsilyloxy)ethoxy)-2-(1-(2,3-dichlorophenyl)-1H-pyrazolo[3,4-d]pyrimidin-4-yloxy)propanoateYield 37.1%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
0 °C

Procedure

Sodium hydride (0.167 g, 4.17 mmol) was added to (S)-methyl 3-(2-(tert-butyldiphenylsilyloxy)ethoxy)-2-hydroxypropanoate (Intermediate AB3) (1.4 g, 3.48 mmol) in anhydrous THF (25 ml) at 0° C. under nitrogen. The resulting solution was stirred at 0° C. for 10 minutes and then 4-chloro-1-(2,3-dichlorophenyl)-1H-pyrazolo[3,4-d]pyrimidine (Intermediate AR2) (1.432 g, 3.83 mmol) was added. The reaction mixture was allowed to warm to room temperature and stirred for 1 hour. The reaction mixture was neutralised with 1M citric acid and the majority of the THF removed in vacuo. The reaction mixture was diluted with water (20 mL) and EtOAc (50 mL). The organic layer was separated and the aqueous layer re-extracted with EtOAc (2×100 mL). The combined organics were washed with saturated brine (75 mL), dried (MgSO4) and evaporated. The crude product was purified by flash silica chromatography, eluting with 50 to 100% EtOAc in isohexane. Fractions containing the product were evaporated to dryness to afford crude product which unfortunately was contaminated with starting alcohol and Methyl glycidate. The crude product was repurified by flash silica chromatography, elution gradient 0 to 30% EtOAc in toluene to afford the product (0.860 g, 37.1%). 1H NMR (400 MHz, CDCl3) δ 1.04 (9H, s), 3.80-3.69 (5H, m), 3.85 (2H, t), 4.15-4.08 (1H, m), 4.20 (1H, dd), 5.87 (1H, dd), 7.48-7.33 (8H, m), 7.75-7.60 (5H, m), 8.32 (1H, s), 8.54 (1H, s). m/z (ES+) (M+H)+=667; HPLC tR=3.8 min.

Workup

  1. temperatureto warm to room temperature
  2. stirringstirred for 1 hour
  3. customthe majority of the THF removed in vacuo
  4. additionThe reaction mixture was diluted with water (20 mL) and EtOAc (50 mL)
  5. customThe organic layer was separated
  6. extractionthe aqueous layer re-extracted with EtOAc (2×100 mL)
  7. washThe combined organics were washed with saturated brine (75 mL)
  8. dry with materialdried (MgSO4)
  9. customevaporated
  10. customThe crude product was purified by flash silica chromatography
  11. washeluting with 50 to 100% EtOAc in isohexane
  12. additionFractions containing the product
  13. customwere evaporated to dryness
  14. customto afford crude product which
  15. customThe crude product was repurified by flash silica chromatography, elution gradient 0 to 30% EtOAc in toluene

Sources & evidence

ORD record
ord-196ffc7737d941f098d3e5bb5ee99401
Source dataset
uspto-grants-2012_03
Patent number
US08143263B2

Reaction notes

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