Iodoethane → 7-Ethyl-5-methoxy-2-(4-methoxyphenyl)-1,3-benzoxazole

HRID 491746Notes

Reaction equation

HRID 491746 reaction equation
[CH2:1]([Li])[CH2:2][CH2:3][CH3:4].BrC1C2[O:14][C:13]([C:16]3[CH:21]=[CH:20][C:19]([O:22][CH3:23])=[CH:18][CH:17]=3)=[N:12][C:11]=2[CH:10]=[C:9]([O:24][CH3:25])[CH:8]=1.ICC>C1COCC1>[CH2:3]([C:2]1[C:1]2[O:14][C:13]([C:16]3[CH:17]=[CH:18][C:19]([O:22][CH3:23])=[CH:20][CH:21]=3)=[N:12][C:11]=2[CH:10]=[C:9]([O:24][CH3:25])[CH:8]=1)[CH3:4]

Participants

5

Reactant 3

HCID 6340IodoethaneHCID 121489697-Bromo-5-methoxy-2-(4-methoxyphenyl)-1,3-benzoxazoleHCID 178418339Butyllithium

Product 1

HCID 114829667-Ethyl-5-methoxy-2-(4-methoxyphenyl)-1,3-benzoxazoleYield 91%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

n-Butyllithium (2.5 N, 0.43 mL, 1.08 mmol) was added dropwise into a cold (−78° C.) mixture of 7-bromo-5-methoxy-2-(4-methoxyphenyl)-1,3-benzoxazole (300 mg, 0.90 mmol) and THF (2 mL). The mixture was allowed to stir for 0.5 h. Iodoethane (0.14 mL, 1.8 mmol) was added dropwise into the mixture. The reaction mixture was allowed to warm to room temperature and stirred for 2 h. The reaction was quenched with aqueous ammonium chloride, poured into water, and extracted with EtOAc. The organic extracts were washed with brine and dried over MgSO4. Evaporation and flash chromatography (20% EtOAc/petroleum ether) gave (231 mg, 91% yield) of the product as a light brown solid: m.p. 85° C.; MS m/e 284 (M+H)+.

Workup

  1. stirringstirred for 2 h
  2. customThe reaction was quenched with aqueous ammonium chloride
  3. additionpoured into water
  4. extractionextracted with EtOAc
  5. washThe organic extracts were washed with brine
  6. dry with materialdried over MgSO4
  7. customEvaporation and flash chromatography (20% EtOAc/petroleum ether)

Sources & evidence

ORD record
ord-1346cc4e34af4b6584e9a4e01ce0ae14
Source dataset
uspto-grants-2009_05
Patent number
US07531564B2

Reaction notes

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