1,3-Dichloroacetone → 4-(ChloroMethyl)-2-cyclopropyloxazole

Temperature

110 °C

A mixture of cyclopropanecarboxylic acid amide (5.0 g, 58.74 mmol) and 1,3-dichloro-propan-2-one (14.92 g, 117.49 mmol) was heated at 110° C. for 4 h. The mixture was cooled to room temperature and water (75 mL) was added and the mixture was extracted with dichloromethane (3×50 mL). The organic layer was dried over anhydrous sodium sulphate and evaporated in vacuo to get crude residue. After purification via column chromatography (100-200 silica gel, elution with 2% EtOAc in hexane), 4 g of 4-chloromethyl-2-cyclopropyl-oxazole was obtained as a dark brown liquid, 158.0 (M+H)+. But it contained impurities. This compound was used for the next step as such.

1. temperatureThe mixture was cooled to room temperature
2. extractionthe mixture was extracted with dichloromethane (3×50 mL)
3. dry with materialThe organic layer was dried over anhydrous sodium sulphate
4. customevaporated in vacuo
5. customto get crude residue
6. customAfter purification
7. washvia column chromatography (100-200 silica gel, elution with 2% EtOAc in hexane)

ORD record

ord-7f32b25d66db48d4ae4be88900cd39c2

Source dataset

uspto-grants-2014_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08729105B2