Ethyl trifluoroacetate → HCID 86693744, compound

Add a solution of n-BuLi (21.6 mL, 2.5 M in hexane, 54.0 mmol) to a solution of 2,3,4,5-tetrachloro-thiophene (10 g, 45.0 mmol) in dry THF (160 mL) at −78° C. and stir the mixture for 2 hours. Add a solution of trifluoro-acetic acid ethyl ester (9.59 g, 67.6 mmol) in THF (15 mL) and stir at −78° C. for additional 2.5 hours. Quench the reaction with saturated NH4Cl solution (100 mL). Extract the aqueous mixture with EtOAc (100 mL×3). The combined organic layers are washed with brine, dried over anhydrous Na2SO4, and evaporate under vacuum. Purify the residue by a flash column on silica gel eluting with PE:EtOAc (10:1 to 5:1) to afford 2,2,2-trifluoro-1-(3,4,5-trichloro-thiophen-2-yl)-ethanone as a brown oil (10.4 g, 81.9%). 13F NMR (400 MHz, CDCl3) δ −73.38 (s, 3F).

1. stirringstir at −78° C. for additional 2.5 hours
2. customQuench
3. customthe reaction with saturated NH4Cl solution (100 mL)
4. extractionExtract the aqueous mixture with EtOAc (100 mL×3)
5. washThe combined organic layers are washed with brine
6. dry with materialdried over anhydrous Na2SO4
7. customevaporate under vacuum
8. customPurify the residue by a flash column on silica gel eluting with PE

ORD record

ord-b6359b842994412ca6a1bc905a2ccf1f

Source dataset

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08648081B2