Ethyl Acrylate → ethyl(E)-3-(3-chloro-6-pyridazinyl)-2-propenoate

Temperature

111 °C

A suspension of 3-chloro-6-iodopyridazine (2.4 g, 10 mmol), ethyl acrylate (4.4 mL, 40 mmol), palladium(II) acetate (90 mg, 0.40 mmol) and tri(o-tolyl)phosphine (366 mg, 1.20 mmol) in DMF (10 mL) and diisopropylethyl amine (5 mL) was stirred with heating (111° C. oil-bath) for 3.5 h, cooled to room temperature, diluted with H2O (50 mL) and extracted with EtOAc (300 mL). The extract was washed (brine) and dried. After solvent removal at reduced pressure, the residue was chromatographed (14% to 20% EtOAc/hexane) to give 174 mg (8%) of ethyl(E)-3-(3-chloro-6-pyridazinyl)-2-propenoate as a brown solid, mp 106-110° C. IR 2928, 1715, 1186 cm−1; 1H NMR (CDCl3) δ 1.38 (t, J=7.5 Hz, 3H, CH2CH3), 4.33 (q, J=7.5 Hz, 2H, CH2CH3), 7.98 (d, J=16.2 Hz, 1H, CH═CHCO), 7.57 (d, J=8.4 Hz, 1H, 4-ArH), 7.63 (d, J=8.4 Hz, 1H, 5-ArH), 7.86 ppm (d, J=16.2 Hz, 1H, CH═CHCO). HRMS calcd C9H9ClN2O2 [M+H]+ 213.0425. found 213.0431.

1. temperaturecooled to room temperature
2. extractionextracted with EtOAc (300 mL)
3. washThe extract was washed (brine)
4. customdried
5. customAfter solvent removal at reduced pressure
6. customthe residue was chromatographed (14% to 20% EtOAc/hexane)

ORD record

ord-25d58a3420ed474c929dd5f616a3bcc3

Source dataset

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09096544B2