2,2-Difluoro-2-(fluorosulfonyl)acetic acid → 4-Difluoromethoxy-pyrrolidine-1,2-dicarboxylic acid 2-[2-(4-bromo-phenyl)-2-oxo-ethyl]ester 1-tert-butyl ester

온도

45 °C

To 4-Hydroxy-pyrrolidine-1,2-dicarboxylic acid 2-[2-(4-bromo-phenyl)-2-oxo-ethyl]ester 1-tert-butyl ester (500 mg) and Cu(I)I (45 mg) in MeCN (8 mL) at 45° C. was added 242 μl of difluoro-fluorosulfonyl-acetic acid in 2 mL of MeCN dropwise for 60 min. The reaction mixture was stirred at 45° C. for 60 min. and evaporated under reduced pressure, and resulting residue was taken up in ethyl acetate (100 mL). The organic phase was washed with brine (1×100 mL) and dried over sodium sulfate. After the solvent was removed, the resulting oil was subjected to silica gel chromatography using effluent of 10-50% ethyl acetate and hexanes. The fractions containing product were combined and the solvent was removed under reduced pressure to provide 4-Difluoromethoxy-pyrrolidine-1,2-dicarboxylic acid 2-[2-(4-bromo-phenyl)-2-oxo-ethyl]ester 1-tert-butyl ester (339 mg, 61%) as a clear oil.

1. customevaporated under reduced pressure
2. customresulting residue
3. washThe organic phase was washed with brine (1×100 mL)
4. dry with materialdried over sodium sulfate
5. customAfter the solvent was removed
6. additionThe fractions containing product
7. customthe solvent was removed under reduced pressure

ORD 기록

ord-9d0314f381b74fb8bb6c9899728cb2cb

출처 데이터셋

uspto-grants-2013_11

DOI

10.6084/m9.figshare.5104873.v1

특허 번호

US08575118B2