4-Bromoaniline → N-(4-Bromophenyl)-3-oxobutanamide

HRID 279993Notes

Reaction equation

[Br:1][C:2]1[CH:8]=[CH:7][C:5]([NH2:6])=[CH:4][CH:3]=1.[CH2:9]=[C:10]1[O:14][C:12](=[O:13])[CH2:11]1.C(OCC)(=O)C>C1(C)C=CC=CC=1>[Br:1][C:2]1[CH:8]=[CH:7][C:5]([NH:6][C:12](=[O:13])[CH2:11][C:10](=[O:14])[CH3:9])=[CH:4][CH:3]=1

Participants

Conditions

Temperature: 55 °C

Procedure

To a stirred solution of 34.14 g (0.200 moles) of 4-bromoaniline in 130 ml toluene under N2, 18.00 g (0.220 moles) of diketene was added dropwise over a 10 minute period followed by 15 ml of toluene. The temperature rose to 80° C. during the addition; the solution was then refluxed 20 minutes, cooled to 55° C. and 60 ml of petroleum ether added. An immediate precipitation occurred. The tan-white crystals were filtered and washed with three 100 ml portions of 1:1 toluene/petroleum ether. The product was taken up in hot absolute ethanol and crystallisation induced by addition of toluene to the ethanolic solution. Three crops of crystals from the ethanol/toluene solvent system gave 22.90 g (43%) and had Rf 0.69 on silica TLC with ethyl acetate; mp 135.8°-137.2° C. Anal. Calcd. for C10H10BrNO2 : C, 46.90; H, 3.94; N, 5.47; Br, 31.20. Found: C, 47.13; H, 4.00; N, 5.46; Br, 31.31.

Workup

additionThe temperature rose to 80° C. during the addition
temperaturethe solution was then refluxed 20 minutes
customAn immediate precipitation
filtrationThe tan-white crystals were filtered
washwashed with three 100 ml portions of 1:1 toluene/petroleum ether
customcrystallisation
additioninduced by addition of toluene to the ethanolic solution
customThree crops of crystals from the ethanol/toluene solvent system gave 22.90 g (43%)

Sources & evidence

ORD record: ord-6a3a41837deb450a9fa8a6c899ca03db
Source dataset: uspto-grants-1986_05
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US04587341

Reaction notes

Loading…