Trimethylamine oxide → 5-Formylbenzofuran-2-carbonitrile

HRID 1773228Notes

Reaction equation

C[N+]([O-:5])(C)C.Br[CH2:7][C:8]1[CH:9]=[CH:10][C:11]2[O:15][C:14]([C:16]#[N:17])=[CH:13][C:12]=2[CH:18]=1>CS(C)=O.O.[Cl-].[Na+].O>[CH:7]([C:8]1[CH:9]=[CH:10][C:11]2[O:15][C:14]([C:16]#[N:17])=[CH:13][C:12]=2[CH:18]=1)=[O:5]

Participants

Conditions

Temperature: 70 °C

Procedure

Trimethlamine-N-oxide (6.75 g, 90 mmol) was added to a solution of 5-(bromomethyl)benzofuran-2-carbonitrile (4.46 g, 18.89 mmol) in 57 mL of DMSO and 6 mL of H2O. The mixture was stirred at 70° C. for 3 hr. After the reaction was cooled to room temperature, the mixture was diluted with 72 mL of brine, and extracted with EtOAc (3×100 mL). The combined organic layers were washed with H2O (2×20 mL), brine, dried over Na2SO4, filtered, and concentrated under reduced pressure. The resulting residue was purified by silica gel flash chromatography, 100% Heptane-30% Ethyl Acetate/70% Heptane, to give 5-formylbenzofuran-2-carbonitrile (1.5 g). 1H NMR (400 MHz, DMSO-d6) δ 7.96 (d, J=8.7 Hz, 1H), 8.12 (dd, J=8.7, 1.7 Hz, 1H), 8.30 (d, J=0.9 Hz, 1H), 8.46 (dd, J=1.6, 0.6 Hz, 1H), 10.11 (s, 1H).

Workup

temperatureAfter the reaction was cooled to room temperature
extractionextracted with EtOAc (3×100 mL)
washThe combined organic layers were washed with H2O (2×20 mL), brine
dry with materialdried over Na2SO4
filtrationfiltered
concentrationconcentrated under reduced pressure
customThe resulting residue was purified by silica gel flash chromatography, 100% Heptane-30% Ethyl Acetate/70% Heptane

Sources & evidence

ORD record: ord-8d05f10c32c148ad85c1b0be6240b586
Source dataset: uspto-grants-2016_02
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09255093B2

Reaction notes

Loading…