Trimethylsilylacetylene → 2,3-dihydro-6-(2-trimethylsilylethynyl)-(4H)-1-benzothiopyran-4-one

HRID 618063Notes

Reaction equation

HRID 618063 reaction equation
Br[C:2]1[CH:3]=[CH:4][C:5]2[S:10][CH2:9][CH2:8][C:7](=[O:11])[C:6]=2[CH:12]=1.[CH3:13][Si:14]([C:17]#[CH:18])([CH3:16])[CH3:15]>C1COCC1.N(CC)CC.[Cu]I.Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1>[CH3:13][Si:14]([CH3:16])([CH3:15])[C:17]#[C:18][C:2]1[CH:3]=[CH:4][C:5]2[S:10][CH2:9][CH2:8][C:7](=[O:11])[C:6]=2[CH:12]=1

Participants

7

Procedure

A solution of 1.00 g (4.11 mmol) 2,3-dihydro-6-bromo-(4H)-1-benzothiopyran-4-one and 78.3 mg (0.41 mmol) CuI in 15.0 ml THF and 6.0 ml Et2NH was sparged with argon for 5 minutes. To this solution was added 2.0 ml (1.39 g, 14.2 mmol) of (trimethylsilyl)acetylene followed by 288.5 mg (0.41 mmol) of bis(triphenylphosphine)palladium(II) chloride. The resulting dark solution was stirred at room temperature for 3 days and then filtered through a pad of Celite, which was washed with EtOAc. The filtrate was washed with H2O and saturated aqueous NaCl before being dried over MgSO4. The title compound was isolated as an orange oil by column chromatography (4% EtOAc-hexanes). 1H NMR (CDCl3): δ 8.13 (1H, d, J=1.9 Hz), 7.36 (1H, dd, J=2.1, 8.2 Hz), 7.14 (1H, d, J=8.2 Hz), 3.19 (2H, d, J=6.3 Hz), 2.91 (2H, d, J=6.3 Hz), 0.21 (9H, s).

Workup

  1. filtrationfiltered through a pad of Celite, which
  2. washwas washed with EtOAc
  3. washThe filtrate was washed with H2O and saturated aqueous NaCl
  4. dry with materialbefore being dried over MgSO4

Sources & evidence

ORD record
ord-ef9059700dc9418da487895a6c6a4fa5
Source dataset
uspto-grants-1999_09
Patent number
US05952345

Reaction notes

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