Phosphorus tribromide → HCID 67491531, compound

HRID 880908Notes

Reaction equation

HRID 880908 reaction equation
[C:1]([N:5]1[CH:9]=[C:8]([CH2:10]O)[C:7]([C:12]([O:14][CH2:15][CH3:16])=[O:13])=[N:6]1)([CH3:4])([CH3:3])[CH3:2].P(Br)(Br)[Br:18]>ClCCl>[Br:18][CH2:10][C:8]1[C:7]([C:12]([O:14][CH2:15][CH3:16])=[O:13])=[N:6][N:5]([C:1]([CH3:4])([CH3:3])[CH3:2])[CH:9]=1

Participants

4

Reactant 2

HCID 24614Phosphorus tribromideHCID 674914531H-Pyrazole-3-carboxylic acid, 1-(1,1-dimethylethyl)-4-(hydroxymethyl)-, ethyl ester

Product 1

HCID 67491531HCID 67491531, compoundYield 82.6%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a 0° C. solution of ethyl 1-tert-butyl-4-(hydroxymethyl)-1H-pyrazole-3-carboxylate (3.9 g, 17.24 mmol) in dichloromethane (120 mL) was added phosphorus tribromide (4.91 mL, 51.7 mmol), and the resultant mixture was stirred 30 minutes at 0° C. and then 1 hour at room temperature. The mixture was quenched with 50 mL water, neutralized with saturated aqueous sodium bicarbonate, stirred 30 minutes, and then extracted with dichloromethane (2×150 mL). The combined organic extracts were washed with 100 mL brine, dried over sodium sulfate, filtered and concentrated. The resulting residue was purified by flash chromatography (7-60% ethyl acetate/heptanes, 50 g silica gel) to yield ethyl 4-(bromomethyl)-1-tert-butyl-1H-pyrazole-3-carboxylate (4.12 g) as a clear oil. +APCI (M+H) 289.1; 1H NMR (400 MHz, CDCl3, δ): 7.61 (s, 1H), 4.70 (s, 2H), 4.41 (q, J=7.2 Hz, 2H), 1.60 (s, 9H), 1.40 (t, 3H).

Workup

  1. custom1 hour
  2. customat room temperature
  3. customThe mixture was quenched with 50 mL water
  4. extractionextracted with dichloromethane (2×150 mL)
  5. washThe combined organic extracts were washed with 100 mL brine
  6. dry with materialdried over sodium sulfate
  7. filtrationfiltered
  8. concentrationconcentrated
  9. customThe resulting residue was purified by flash chromatography (7-60% ethyl acetate/heptanes, 50 g silica gel)

Sources & evidence

ORD record
ord-f165a53e4baf455dbb1415304f4f774d
Source dataset
uspto-grants-2015_03
Patent number
US08993586B2

Reaction notes

Loading…