cis-5-[3,5-Bis(trifluoromethyl)phenyl]-4-ethenyl-1,3-oxazolidin-2-one → (4S,5R)-5-[3,5-bis(trifluoromethyl)phenyl]-3-{(1S)-1-[2-bromo-5-(trifluoromethyl)phenyl]prop-2-en-1-yl}-4-ethenyl-1,3-oxazolidin-2-one

Participants

Reaction Conditions

Reaction Steps

To a 500 mL RBF was added 1-(2-bromo-5-fluorophenyl)prop-2-en-1-yl ethyl carbonate (10.4 g, 29.5 mmol), (4S,5R)-5-[3,5-bis(trifluoromethyl)phenyl]-4-ethenyl-1,3-oxazolidin-2-one (4 g, 12.3 mmol), DCM (20 mL), and the Helmchen dibenzo[a,e]cyclooctatetraene (dbcot) iridium phosphoramidite catalyst complex (407 mg, 0.369 mmol) (Helmchen et al, Chem. Eur. J., 2010, 16, 6601-6615). The reaction was stirred at 33° C. for 2 days open to air. The reaction was filtered over Celite and purified by column chromatography to yield (4S,5R)-5-[3,5-bis(trifluoromethyl)phenyl]-3-{(1S)-1-[2-bromo-5-(trifluoromethyl)phenyl]prop-2-en-1-yl}-4-ethenyl-1,3-oxazolidin-2-one (4.5 g, 7.65 mmol). 1H NMR (500 MHz, CDCl3) δ7.86 (m, 2H), 7.68 (s, 2H), 7.64 (s, 1H), 7.54 (d, J=6.5 Hz, 1H), 6.22 (m, 1H), 5.75 (m, 2H), 5.43 (m, 2H), 5.20 (m, 1H), 5.03 (d, J=5.0 Hz, 1H), 4.8 (d, J=8.5 Hz, 1H), 4.1 (m, 1H).

Provenance & Evidence