Trimethylsilylacetylene → 4-(Trimethylsilylethynyl)benzaldehyde

HRID 915731

Reaction equation

HRID 915731 reaction equation
Br[C:2]1[CH:9]=[CH:8][C:5]([CH:6]=[O:7])=[CH:4][CH:3]=1.[C:10]([Si:12]([CH3:15])([CH3:14])[CH3:13])#[CH:11]>C(N(CC)CC)C.C([O-])(=O)C.[Pd+2].C([O-])(=O)C.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>[CH3:13][Si:12]([C:10]#[C:11][C:2]1[CH:9]=[CH:8][C:5]([CH:6]=[O:7])=[CH:4][CH:3]=1)([CH3:15])[CH3:14]

Participants

6

Reactant 2

HCID 66111TrimethylsilylacetyleneHCID 707414-Bromobenzaldehyde

Product 1

HCID 27716434-(Trimethylsilylethynyl)benzaldehydeYield 96.1%

Reagents, catalysts & solvents 3

HCID 11776TriphenylphosphineCatalystHCID 167845palladium(II) acetateCatalystHCID 8471TriethylamineSolvent

Procedure

To a solution of 4-bromobenzaldehyde (10.00 g, 54.08 mmol) and triphenylphosphine (0.500 g, 1.91 mmol) in anhydrous triethylamine (80 mL) under argon were added ethynyltrimethylsilane (6.00 g, 61.09 mmol) and palladium (II) acetate (0.100 g, 0.445 mmol). The final mixture was heated to reflux for 2 hours, and was then cooled to room temperature and filtered. The filtrate was concentrated under vacuum to a thick oil, which was purified by column chromatography (dichloromethane/petroleum ether 1:4) and recrystallized from cold cyclohexane to give 10.5 g (96.1% yield) of 4-(trimethylsilylethynyl)benzaldehyde [MS m/e 187.2 (M+); 1H-NMR (CDCl3) δ ppm: 0.27 (s, 9H, SiMe3), 7.60 (d, 2H, ArH, J=8.1 Hz), 7.82 (d, 2H, ArH, J=8.1 Hz), 10.00 (s, 1H, CHO)]. This compound (8.00 g, 39.59 mmol) was treated with K2CO3 (0.500 g) in methanol (50 mL) at 25° C. for 2 hours under Argon. The solvent was removed under vacuum, and the residue was dissolved in dichloromethane (100 mL). This solution was washed once with a saturated aqueous NaHCO3 solution, and once with water, was then dried over anhydrous Na2SO4, and the solvent was evaporated under vacuum. The yellow residue was purified by column chromatography using dichloromethane/petroleum ether 1:4, and then recrystallized from cold cyclohexane to give 4.40 g (85.5% yield) of the title compound; MS (EI) m/e 130.0; (M+). 1H-NMR (CDCl3) δ ppm: 3.30 (s, 1H, CH), 7.64 (d, 2H, ArH, J=8.1 Hz), 7.84 (d, 2H, ArH, J=8.1 Hz), 10.02 (s, 1H, CHO).

Workup

  1. temperatureto reflux for 2 hours
  2. filtrationfiltered
  3. concentrationThe filtrate was concentrated under vacuum to a thick oil, which
  4. customwas purified by column chromatography (dichloromethane/petroleum ether 1:4)
  5. customrecrystallized from cold cyclohexane

Sources & evidence

ORD record
ord-4e6a0c692b97473984396a4126dd40fa
Source dataset
uspto-grants-2007_09
Patent number
US07267990B2

Linked notes

Loading…