Methanol → 5-(4-Benzyloxy-phenyl)-6-cyclohexyl-7-methoxy-pyrazolo[1,5-a]pyrimidine-2-carboxylic acid methyl ester

HRID 270970Notes

Reaction equation

HRID 270970 reaction equation
[CH3:1][O:2][C:3]([C:5]1[CH:34]=[C:8]2[NH:9][C:10]([C:20]3[CH:25]=[CH:24][C:23]([O:26][CH2:27][C:28]4[CH:33]=[CH:32][CH:31]=[CH:30][CH:29]=4)=[CH:22][CH:21]=3)=[C:11]([CH:14]3[CH2:19][CH2:18][CH2:17][CH2:16][CH2:15]3)[C:12](=[O:13])[N:7]2[N:6]=1)=[O:4].CO.[C:37]1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.N(C(OC(C)C)=O)=NC(OC(C)C)=O>O1CCCC1>[CH3:1][O:2][C:3]([C:5]1[CH:34]=[C:8]2[N:9]=[C:10]([C:20]3[CH:21]=[CH:22][C:23]([O:26][CH2:27][C:28]4[CH:29]=[CH:30][CH:31]=[CH:32][CH:33]=4)=[CH:24][CH:25]=3)[C:11]([CH:14]3[CH2:19][CH2:18][CH2:17][CH2:16][CH2:15]3)=[C:12]([O:13][CH3:37])[N:7]2[N:6]=1)=[O:4]

Participants

6

Reactant 4

HCID 887MethanolHCID 11776TriphenylphosphineHCID 75555Diisopropyl diazene-1,2-dicarboxylateHCID 178497016HCID 178497016, compound

Product 1

HCID 588250375-(4-Benzyloxy-phenyl)-6-cyclohexyl-7-methoxy-pyrazolo[1,5-a]pyrimidine-2-carboxylic acid methyl esterYield 106%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To an ice cold mixture of 22 mg (0.048 mmol) of 5-(4-benzyloxy-phenyl)-6-cyclohexyl-7-oxo-4,7-dihydro-pyrazolo[1,5-a]pyrimidine-2-carboxylic acid methyl ester in 3 mL of tetrahydrofuran (THF) was added 0.008 mL (0.192 mmol) of methanol (MeOH), 50 mg (0.192 mmol) of triphenylphosphine (PPh3), followed by 0.038 mL (0.192 mmol) of diisopropyl azodicarboxylate (DIAD) and the mixture was allowed to warm up to rt and stirred at rt for 2 h when analysis by thin layer chromatography (TLC) revealed complete consumption of starting material. The reaction mixture was then concentrated and the residue was chromatographed on silica gel (Biotage; gradient elution dichloromethane (DCM) to 10% ethyl acetate in DCM) to give 24 mg of desired 5-(4-benzyloxy-phenyl)-6-cyclohexyl-7-methoxy-pyrazolo[1,5-a]pyrimidine-2-carboxylic acid methyl ester as indicated by 1H-NMR (containing traces of impurities).

Workup

  1. customconsumption of starting material
  2. concentrationThe reaction mixture was then concentrated
  3. customthe residue was chromatographed on silica gel (Biotage; gradient elution dichloromethane (DCM) to 10% ethyl acetate in DCM)

Sources & evidence

ORD record
ord-a8e9c6e6fba74068b609c29071bad66f
Source dataset
uspto-grants-2008_11
Patent number
US07449488B2

Reaction notes

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