Triphenylphosphine → ethyl 1-{2-[(tert-butoxycarbonyl)amino]ethyl}-3-{[tert-butyl(dimethyl)silyl]oxy}-1H-pyrazole-5-carboxylate

HRID 571720Notes

Reaction equation

HRID 571720 reaction equation
N(C(OC(C)(C)C)=O)=NC(OC(C)(C)C)=O.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.O[CH2:37][CH2:38][NH:39][C:40](=[O:46])[O:41][C:42]([CH3:45])([CH3:44])[CH3:43].[Si:47]([O:54][C:55]1[NH:59][N:58]=[C:57]([C:60]([O:62][CH2:63][CH3:64])=[O:61])[CH:56]=1)([C:50]([CH3:53])([CH3:52])[CH3:51])([CH3:49])[CH3:48]>C1COCC1>[C:42]([O:41][C:40]([NH:39][CH2:38][CH2:37][N:58]1[C:57]([C:60]([O:62][CH2:63][CH3:64])=[O:61])=[CH:56][C:55]([O:54][Si:47]([C:50]([CH3:51])([CH3:53])[CH3:52])([CH3:49])[CH3:48])=[N:59]1)=[O:46])([CH3:45])([CH3:44])[CH3:43]

Participants

6

Reactant 4

HCID 11776TriphenylphosphineHCID 97268Di-tert-butyl azodicarboxylateHCID 2733206tert-butyl N-(2-hydroxyethyl)carbamateHCID 178469392HCID 178469392, compound

Product 1

HCID 86706487ethyl 1-{2-[(tert-butoxycarbonyl)amino]ethyl}-3-{[tert-butyl(dimethyl)silyl]oxy}-1H-pyrazole-5-carboxylateYield 94.3%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
80 °C

Procedure

Di-tert-butyl azodicarboxylate (1.07 g, 4.66 mmol) was added to a stirred solution of triphenylphosphine (1.22 g, 4.66 mmol), tert-butyl N-(2-hydroxyethyl)carbamate (0.8 mL, 5.18 mmol) and ethyl 5-{[tert-butyl(dimethyl)silyl]oxy}-1H-pyrazole-3-carboxylate (0.7 g, 2.59 mmol) in THF (22 mL). The mixture was stirred at 80° C. for 16 hours and the solvents evaporated in vacuo. The crude product was purified by flash column chromatography (silica; AcOEt in heptane 0/100 to 30/70). The desired fractions were collected and the solvents evaporated in vacuo to yield ethyl 1-{2-[(tert-butoxycarbonyl)amino]ethyl}-3-{[tert-butyl(dimethyl)silyl]oxy}-1H-pyrazole-5-carboxylate (1.01 g, 94% yield) as a white solid.

Workup

  1. customthe solvents evaporated in vacuo
  2. customThe crude product was purified by flash column chromatography (silica; AcOEt in heptane 0/100 to 30/70)
  3. customThe desired fractions were collected
  4. customthe solvents evaporated in vacuo

Sources & evidence

ORD record
ord-1714cd116e44412681a508e87ab50d88
Source dataset
uspto-grants-2015_05
Patent number
US09029366B2

Reaction notes

Loading…