Dichloromethane → Methyl 2-(dichloromethyl)-4,5-dihydro-1,3-oxazole-4-carboxylate

A solution of dichloroacetonitrile (215 g, 1.96 mol) in methanol (200 mL) was added drop-wise to a −5° C. solution of sodium methoxide (15.4 g, 0.285 mol) in methanol (500 mL). A solution of ethyl serinate, hydrochloride salt (382 g, 2.45 mol) in methanol (300 mL) was then added to the −5° C. reaction mixture, which was subsequently allowed to stir at room temperature for 16 hours. Dichloromethane (1 L) and water (800 mL) were added, and the aqueous layer was extracted with dichloromethane (1 L); the combined organic layers were concentrated in vacuo to provide the product as a yellow oil, which was used in the next step without additional purification. Yield: 300 g, 1.4 mol, 71%. 1H NMR (400 MHz, CDCl3) δ 6.29 (s, 1H), 4.90 (dd, J=10.8, 8.3 Hz, 1H), 4.74 (dd, J=8.8, 8.3 Hz, 1H), 4.66 (dd, J=10.8, 8.9 Hz, 1H), 3.82 (s, 3H).

1. extractionthe aqueous layer was extracted with dichloromethane (1 L)
2. concentrationthe combined organic layers were concentrated in vacuo

ORD record

ord-573170a9a23241e2a6f875a3d7313085

Source dataset

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09315520B2