1-Bromo-3-methylbutane → HCID 68874755, compound

HRID 2224952Notes

Reaction equation

HRID 2224952 reaction equation
[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([CH:9]([CH3:14])[C:10]([O:12][CH3:13])=[O:11])=[CH:5][CH:4]=1.CN(C)P(=O)(N(C)C)N(C)C.[CH:26]([N-]C(C)C)(C)C.[Li+].BrC[CH2:36][CH:37]([CH3:39])[CH3:38]>O1CCCC1>[CH3:1][O:2][C:3]1[CH:4]=[CH:5][C:6]([C:9]([CH3:26])([CH2:14][CH2:36][CH:37]([CH3:39])[CH3:38])[C:10]([O:12][CH3:13])=[O:11])=[CH:7][CH:8]=1

Participants

6

Reactant 4

HCID 78911-Bromo-3-methylbutaneHCID 12679HexamethylphosphoramideHCID 2724682Lithium diisopropylamideHCID 12398855Methyl 2-(4-methoxyphenyl)propanoate

Product 1

HCID 68874755HCID 68874755, compoundYield 92%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a solution of Example 155A (15 g. 77.2 mmol) and hexamethylphosphoric triamide (14.8 mL, 77.2 mmol) in 200 mL anhydrous tetrahydrofuran was added 2 M lithium diisopropyl amide (45 mL, 90 mmol) while maintaining the temperature below −70° C. After 30 minutes at −78° C., 1-bromo-3-methylbutane (10.6 mL, 85 mmol) was added and the reaction stirred for 16 hours at room temperature. Most of the solvent was removed under vacuum and the residue partitioned between ethyl acetate and 1 N HCl. The crude product was purified on silica using 5% ethyl acetate in hexanes to give the product as a colorless oil (18.6 g, 92%). 1H NMR (300 MHz, CDCl3) δ ppm 0.86 (d, J=5.15 Hz, 3 H) 0.88 (d, J=5.15 Hz, 3 H) 1.04 (m, 2 H) 1.51 (m, 1 H) 1.51 (s, 3 H) 1.88 (ddd, J=13.33, 10.57, 6.25 Hz, 1 H) 2.02 (m, 1 H) 3.64 (s, 3 H) 3.79 (s, 3 H) 6.85 (m, 2 H) 7.23 (m, 2 H).

Workup

  1. temperaturewhile maintaining the temperature below −70° C
  2. customMost of the solvent was removed under vacuum
  3. customthe residue partitioned between ethyl acetate and 1 N HCl
  4. customThe crude product was purified on silica using 5% ethyl acetate in hexanes

Sources & evidence

ORD record
ord-6b9450ede878426f9a33d616a59ee3e9
Source dataset
uspto-grants-2008_05
Patent number
US07378414B2

Reaction notes

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