Citric Acid → HCID 117628044, compound

Temperature

0 °C

4-hydroxypiperidine (8.14 g, 80.5 mmol) and triethylamine (12.5 mL, 89.6 mmol) were dissolved in anhydrous dichloromethane (50 mL) and cooled to 0° C. A dichloromethane solution (30 mL) of trimethyl acetyl chloride (9.0 mL, 82.4 mmol) was then added slowly, drop wise, and then the mixture was slowly warmed to 23° C. over 3 h. The mixture was then cooled back down to 0° C., more triethylamine (12.5 mL, 89.6 mmol) was added, followed by the slow, drop wise addition of methacrylyl chloride (8.7 mL, 89.0 mmol). 4-methoxyphenol (12.3 mg, x mmol) was added and the reaction was allowed to slowly warm to 23° C. After stirring overnight, the reaction mixture was successively washed 50 mL portions of deionized water, 1 M NaOH, deionized water, 5% citric acid, and brine. After drying over sodium sulfate and filtering, the product was concentrated by rotary evaporation and dried in vacuo to give a brown solid. The solid was triturated with hexanes, filtered, washed with hexanes, and dried in vacuo to give 1-pivaloylpiperidin-4-yl methacrylate as a beige solid (1.87 g, 9%). The filtrate was concentrated by rotary evaporation and purified by flash chromatography on silica gel (eluting with ethyl acetate:hexanes (1:4-1:1)) to give a second batch of 1-pivaloylpiperidin-4-yl methacrylate as a pale yellow solid (6.77 g, 33%).

1. temperaturethe mixture was slowly warmed to 23° C. over 3 h
2. additionwas added
3. temperatureto slowly warm to 23° C
4. dry with materialAfter drying over sodium sulfate
5. filtrationfiltering
6. concentrationthe product was concentrated by rotary evaporation
7. customdried in vacuo
8. customto give a brown solid
9. customThe solid was triturated with hexanes
10. filtrationfiltered
11. washwashed with hexanes
12. customdried in vacuo

ORD record

ord-24a74260859f4923a2b763025da1e91d

Source dataset

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09069275B2