Methyl trifluoroacetate → 2-(trifluoromethyl)-4H-pyran-4-one

To a mixture of KOtBu (729 mg, 6.49 mmol) in diethyl ether (10 mL) at 5° C. were added methyl 2,2,2-trifluoroacetate (767 mg, 5.99 mmol) and (E)-4-methoxybut-3-en-2-one (500 mg, 4.99 mmol). The reaction mixture was stirred at rt for 3 h, and quenched with water and then extracted with ether. Combined organic portions were dried over Na2SO4, filtered and concentrated. The residue was dissolved in isopropanol (150 mL) and 35% solution of hydrochloric acid (0.5 mL) and refluxed for 45 min. Then the solution was concentrated to remove alcohol and fractionated at reduced pressure to get the title product as yellow oil.

1. customquenched with water
2. extractionextracted with ether
3. dry with materialCombined organic portions were dried over Na2SO4
4. filtrationfiltered
5. concentrationconcentrated
6. dissolutionThe residue was dissolved in isopropanol (150 mL)
7. temperature35% solution of hydrochloric acid (0.5 mL) and refluxed for 45 min
8. concentrationThen the solution was concentrated
9. customto remove alcohol

ORD record

ord-33fdbfda906549c48809e5d1dae35fa8

Source dataset

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08975400B2