Methyl 2-bromo-4-methylbenzoate → Methyl 2-ethenyl-4-methylbenzoate

HRID 514516Notes

Reaction equation

HRID 514516 reaction equation
Br[C:2]1[CH:11]=[C:10]([CH3:12])[CH:9]=[CH:8][C:3]=1[C:4]([O:6][CH3:7])=[O:5].[K+].[CH:14]([B-](F)(F)F)=[CH2:15]>C(O)CC.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2]>[CH:14]([C:2]1[CH:11]=[C:10]([CH3:12])[CH:9]=[CH:8][C:3]=1[C:4]([O:6][CH3:7])=[O:5])=[CH2:15]

Participants

5

Reactant 2

HCID 21779704Methyl 2-bromo-4-methylbenzoateHCID 23679353Potassium vinyltrifluoroborate

Product 1

HCID 21779699Methyl 2-ethenyl-4-methylbenzoateYield 61.3%

Reagents, catalysts & solvents 2

HCID 178418228Bis(cyclopenta-1,4-dien-1-yl(diphenyl)phosphane);dichloropalladium;iron(2+)CatalystHCID 10311-PropanolSolvent

Conditions

Temperature
100 °C

Procedure

A mixture of methyl 2-bromo-4-methylbenzoate (1.06 g, 4.63 mmol), vinyltrifluoroborate potassium salt (621 mg, 4.63 mmol), Pd(dppf)Cl2 (203 mg, 0.28 mmol) and TEA (1.40 g, 13.89 mmol) in n-PrOH (11 mL) was purged with nitrogen, and heated to 100° C. for 2 h. It was then cooled to room temperature and filtered, the filtrate was extracted with ethyl acetate twice. Organic extract was concentrated and purified by flash column chromatograph to give 500 mg of the title compound (60%). 1H NMR (400 MHz, CDCl3): δ 2.40 (3H, s), 3.88 (3H, s), 5.33 (1H, dd, J=1.2 Hz, 10.8 Hz), 5.62 (1H, dd, J=1.2 Hz, 17.6 Hz), 7.12 (1H, d, J=8.0 Hz), 7.37 (1H, s), 7.48 (1H, dd, J=10.8 Hz, 17.6 Hz), 7.80 (1H, d, J=8.0 Hz).

Workup

  1. customwas purged with nitrogen
  2. temperatureIt was then cooled to room temperature
  3. filtrationfiltered
  4. extractionthe filtrate was extracted with ethyl acetate twice
  5. extractionOrganic extract
  6. concentrationwas concentrated
  7. custompurified by flash column chromatograph

Sources & evidence

ORD record
ord-6a867912da4341508747db41bf3f26ee
Source dataset
uspto-grants-2015_08
Patent number
US09107916B2

Reaction notes

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