3-Chlorobenzaldehyde → Ethyl 3-(3-chlorophenyl)-2-propenoate

HRID 1663560Notes

Reaction equation

[Cl:1][C:2]1[CH:3]=[C:4]([CH:7]=[CH:8][CH:9]=1)[CH:5]=O.C1(P(=[CH:29][C:30]([O:32][CH2:33][CH3:34])=[O:31])(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>C1COCC1>[Cl:1][C:2]1[CH:3]=[C:4]([CH:5]=[CH:29][C:30]([O:32][CH2:33][CH3:34])=[O:31])[CH:7]=[CH:8][CH:9]=1

Participants

Conditions

Temperature: 0 °C

Procedure

In a 2 l three necked flask fitted with mechanical stirrer and dropping funnel under inert atmosphere, 106.2 g (755 mmoles, 1 eq) of 3-chlorobenzaldehyde are dissolved in 1 l of THF and cooled down to 0° C. 341.9 g (980 mmoles, 1.3 eq) of ethyl (triphenylphosphoranylidene)acetate are then added under efficient stirring, the temperature raising to 10° C. The mixture is kept under stirring one hour at 0° C., and then overnight at room temperature. The mixture is concentrated to dryness, the residue suspended in diethyl ether, the triphenylphosphine oxide is filtered off and the filtrate concentrated to dryness. The residue is purified by PrepLC (1 kg SiO2, pet. ether/EtOAc, 75:35) to give 191.8 g of pure 375, 92% yield. 1H NMR (250 MHz, (CD3)2SO): 1.30 (t, 3H), 4.25 (q, 2H), 6.70 (d, 1H), 7.40 (m, 2H), 7.50-7.70 (m, 2H), 7.85 (s(broad), 1H).

Workup

temperaturethe temperature raising to 10° C
customovernight
customat room temperature
concentrationThe mixture is concentrated to dryness
filtrationthe triphenylphosphine oxide is filtered off
concentrationthe filtrate concentrated to dryness
customThe residue is purified by PrepLC (1 kg SiO2, pet. ether/EtOAc, 75:35)
customto give 191.8 g of pure 375, 92% yield

Sources & evidence

ORD record: ord-30432ab6953e43109a85315a6390d63b
Source dataset: uspto-grants-2011_10
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08034958B2

Reaction notes

Loading…