Chloroacetyl chloride → (5R)-5-Ethyl-3-morpholinone

Temperature

110 °C

NaH (1.51 g, 37.9 mmol) in dry toluene (10 mL) was cooled to 0° C. under nitrogen, and (2R)-2-amino-1-butanol (1.5 g, 16.8 mmol) in toluene (5 mL) was added dropwise. The mixture was stirred for 20 minutes warming up to room temperature, and chloroacetyl chloride (1.5 mL, 18.9 mmol) in toluene (5 mL) was added dropwise. An exotherm was observed so the mixture was cooled in an ice bath during the addition. After the addition was completed, the reaction mixture was heated to 110° C. overnight. The mixture was cooled to room temperature and 5 g of ammonium chloride were added portionwise. The mixture was stirred for 20 minutes and filtered. The filter cake was washed with toluene and discarded. The filtrate was concentrated to give an orange oil that was dissolved in CH2Cl2 and purified by SiO2 chromatography (gradient: 100% CH2Cl2 to 90:10:1 CH2Cl2/CH3OH/NH4OH) to afford the title compound (1.2 g) as a yellow solid. 1H NMR (400 MHz, CDCl3): δ 0.96 (t, J=7.6 Hz, 3H), 1.52-1.63 (m, 2H), 3.40-3.51 (m, 2H), 3.85-3.94 (m, 1H), 4.07-4.20 (m, 2H), 7.55 (bs, 1H).

1. additionwas added dropwise
2. temperaturewas cooled in an ice bath during the addition
3. additionAfter the addition
4. temperatureThe mixture was cooled to room temperature
5. stirringThe mixture was stirred for 20 minutes
6. filtrationfiltered
7. washThe filter cake was washed with toluene
8. concentrationThe filtrate was concentrated
9. customto give an orange oil that
10. custompurified by SiO2 chromatography (gradient: 100% CH2Cl2 to 90:10:1 CH2Cl2/CH3OH/NH4OH)

ORD record

ord-9d6602d3fa494f1eab5997eaa163b733

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08697685B2