Carbon tetrabromide → Methyl 3-bromomethyl-5-tert-butylbenzoate

HRID 2414472Notes

Reaction equation

HRID 2414472 reaction equation
[C:1]([C:5]1[CH:6]=[C:7]([CH:12]=[C:13]([CH2:15]O)[CH:14]=1)[C:8]([O:10][CH3:11])=[O:9])([CH3:4])([CH3:3])[CH3:2].C(Br)(Br)(Br)[Br:18].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>ClCCl>[Br:18][CH2:15][C:13]1[CH:12]=[C:7]([CH:6]=[C:5]([C:1]([CH3:4])([CH3:3])[CH3:2])[CH:14]=1)[C:8]([O:10][CH3:11])=[O:9]

Participants

5

Reactant 3

HCID 11205Carbon tetrabromideHCID 11776TriphenylphosphineHCID 12144659Methyl 3-tert-butyl-5-(hydroxymethyl)benzoate

Product 1

HCID 12144660Methyl 3-bromomethyl-5-tert-butylbenzoateYield 99%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a solution of methyl 3-tert-butyl-5-hydroxymethylbenzoate VII (9.50 g, 42.7 mmol) and carbon tetrabromide (17.25 g, 52.0 mmol) in dichloromethane (50 mL) was slowly added triphenylphosphine (13.6 g, 52.0 mmol) over the period of 20 minutes, and the mixture was stirred at room temperature for 25 minutes. The reaction mixture was concentrated under reduced pressure and the residue was suspended in ethyl acetate. The precipitate was removed by filtration and the filtrate was concentrated. The crude material was purified by a silica gel chromatography (hexanes/ethyl acetate, 4:1), and the product was re-crystallized form ethyl acetate/hexanes to afford methyl 3-bromomethyl-5-tert-butylbenzoate VIII (12.0 g, 42.1 mmol, 99%) as a white solid: 1H NMR (CDCl3) δ 1.45 (s, 9H), 3.7 (s, 3H), 4.4 (s, 2H), 7.6 (s, 1H), 7.8 (s, 1H), 8.0 (s, 1H); 13C NMR (CDCl3) δ 31.3 (3C), 33.2, 36.0, 52.3, 126.9, 127.5, 130.6, 130.7, 137.9, 152.4, 167.0.

Workup

  1. customover the period of 20 minutes
  2. concentrationThe reaction mixture was concentrated under reduced pressure
  3. customThe precipitate was removed by filtration
  4. concentrationthe filtrate was concentrated
  5. customThe crude material was purified by a silica gel chromatography (hexanes/ethyl acetate, 4:1)
  6. customthe product was re-crystallized form ethyl acetate/hexanes

Sources & evidence

ORD record
ord-49a3a6a3c7344b2395af3e363da82fa5
Source dataset
uspto-grants-2004_11
Patent number
US06812364B2

Reaction notes

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