Methyl propiolate → 2-Hydroxy-7,8-dihydro-5(6H)-quinolinone

Temperature

105 °C

Methyl propiolate (5.03 ml, 56.2 mmol) was added to finely ground 3-aminocyclohex-2-enone (5 g, 45.0 mmol). The resulting mixture was heated to 105° C. resulting in a dark brown solution and stirred under reflux for 60 min. Then the reflux condenser was removed and the excess methyl propiolate was distilled off by raising the temperature to 170° C. The reaction mixture was cooled to RT and the resulting solid was triturated with dichloromethane (10 mL) and heated to 40° C. for 25 min. The hot mixture was filtered and the yellow residue was washed with dichloromethane (10 mL). The solid was dried under reduced pressure. Amount 2.07 g. Yield 28%.

1. customresulting in a dark brown solution
2. temperatureunder reflux for 60 min
3. customThen the reflux condenser was removed
4. distillationthe excess methyl propiolate was distilled off
5. temperatureby raising the temperature to 170° C
6. temperatureThe reaction mixture was cooled to RT
7. customthe resulting solid was triturated with dichloromethane (10 mL)
8. temperatureheated to 40° C. for 25 min
9. filtrationThe hot mixture was filtered
10. washthe yellow residue was washed with dichloromethane (10 mL)
11. customThe solid was dried under reduced pressure

ORD record

ord-83c47424a98f4ae5a244b6a5441f7bda

Source dataset

uspto-grants-2016_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09266855B2