Allyltributylstannane → 5-allyl-2-benzofuran-1(3H)-one

HRID 1186921Notes

Reaction equation

HRID 1186921 reaction equation
Br[C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[C:7](=[O:8])[O:6][CH2:5]2.[CH2:12]([Sn](CCCC)(CCCC)CCCC)[CH:13]=[CH2:14].[Cl-].[Li+]>C1(C)C=CC=CC=1>[CH2:14]([C:2]1[CH:11]=[CH:10][C:9]2[C:7](=[O:8])[O:6][CH2:5][C:4]=2[CH:3]=1)[CH:13]=[CH2:12]

Participants

5

Reactant 3

HCID 90628AllyltributylstannaneHCID 433294Lithium ChlorideHCID 6031445-Bromophthalide

Product 1

HCID 666439845-allyl-2-benzofuran-1(3H)-one

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Conditions

Temperature
100 °C

Procedure

A 4-neck, 22-L, round bottom flask equipped with a mechanical stirrer, thermocouple, nitrogen bubbler, and condenser was charged with 5-bromophthalide (650 g, 3.0 mol), allyltri-n-butyltin (1200 g, 3.6 mol), palladium tetrakis triphenylphosphine (100 g, 0.089 mol), lithium chloride (250 g, 5.9 mol) and toluene (8.8 L). The mixture was evacuated and flushed with nitrogen 3 times and then was stirred at 100° C. for 4 hours. After slowly cooling to ambient temperature, the mixture was filtered and concentrated. The resulting solid was purified by silica gel column chromatography (heptane:ethyl acetate, 0→40%) to provide 5-allyl-2-benzofuran-1(3H)-one. 1H NMR (500 MHz, CD3OD) δ 7.83 (d, J=8.0 Hz, 1H), 7.38 (d, J=8.0 Hz, 1H), 7.33 (s, 1H), 5.98 (m, 1H), 5.29 (s, 2H), 5.11-5.18 (m, 2H), 3.52 (d, J=8.2 Hz, 2H); LC/MS: [(M+1)]+=175.1; tR=2.9 min.

Workup

  1. customThe mixture was evacuated
  2. customflushed with nitrogen 3 times
  3. temperatureAfter slowly cooling to ambient temperature
  4. filtrationthe mixture was filtered
  5. concentrationconcentrated
  6. customThe resulting solid was purified by silica gel column chromatography (heptane:ethyl acetate, 0→40%)

Sources & evidence

ORD record
ord-0306834d6bd2419a828622b2a03b974e
Source dataset
uspto-grants-2014_03
Patent number
US08673920B2

Reaction notes

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