1,1-Dichloroethane → 3,5-Dimethyl-1H-pyrrole-2-carbaldehyde

HRID 1857556Notes

Reaction equation

Cl[CH:2](Cl)[CH3:3].P(Cl)(Cl)(Cl)=[O:6].[CH3:10][C:11]1[NH:12]C=[C:14]([CH3:16])[CH:15]=1>CN(C)C=O>[CH3:10][C:11]1[NH:12][C:2]([CH:3]=[O:6])=[C:14]([CH3:16])[CH:15]=1

Participants

Conditions

Temperature: 0 °C

Procedure

To a solution dimethylformamide (80.4 g) and 1 L of dichloroethane at 0° C. was added phosphorous oxychoride (153.3 g) over a few minutes and the reaction stirred for 1-2 hr at 0° C. 2,4-Dimethylpyrrole (114.6 g) was added dropwise to the above solution at temperature below 5° C. After the addition was complete the reaction was heated and the aqueous layer isolated and saved. The organic layer was extracted again with 300 mL of water and the two aqueous layers combined. The aqueous phase was extracted with 200 mL of dichloroethane and the organic layer discarded. The aqueous phase was cooled to 10° C. and adjusted to pH 10 with 10% sodium hydroxide. The mixture was stirred at 10° C. for 2 hr. The yellow solid was collected by vacuum filtration and washed thoroughly with water. The solid was dried at room temperature under vacuum to give 110.8 g (90% yield of 2,4-dimethyl-5-formylpyrrole.

Workup

additionAfter the addition
temperaturewas heated
customthe aqueous layer isolated
extractionThe organic layer was extracted again with 300 mL of water
extractionThe aqueous phase was extracted with 200 mL of dichloroethane
temperatureThe aqueous phase was cooled to 10° C.
stirringThe mixture was stirred at 10° C. for 2 hr
filtrationThe yellow solid was collected by vacuum filtration
washwashed thoroughly with water
customThe solid was dried at room temperature under vacuum

Sources & evidence

ORD record: ord-d48d46ab343c4bcb87ee9b5575eef1a7
Source dataset: uspto-grants-2000_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06147106

Reaction notes

Loading…