Reaktion #2006484

Reaktionsgleichung

compound 20a

4-[3,3,4-trimethyl-2,5-dioxo-4-(2-hydroxy-ethyl)-1-pyrrolidinyl]-2-trifluoromethyl-benzonitrile

triphenylphosphine

carbontetrabromide

→

desired compound 21a

Ausbeute 40.0%

4-[3,3,4-trimethyl-2,5-dioxo-4-(2-bromo-ethyl)-1-pyrrolidinyl]-2-trifluoromethyl-benzonitrile

Ausbeute 40.0%

Lösungsmittel

dichloromethane

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeto return to room temperature
2. 2
   Filtrationfiltered on a cotton plug
3. 3
   SonstigePurification of the resulting crude product by flash chromatography

Vorschrift

To a solution of compound 20a (33 mg, 0.097 mmol) in anhydrous dichloromethane (2 mL) at 0° C. under argon were added triphenylphosphine (50 mg, 0.194 mmol) and carbontetrabromide (64 mg, 0.194 mmol). The solution was allowed to return to room temperature and stirred for 1 hr. The resulting solution was diluted with dichloromethane (25 mL) and filtered on a cotton plug. Purification of the resulting crude product by flash chromatography using a gradient of ethyl acetate/hexane (3:97 to 3:7) as an eluant gave the desired compound 21a (15 mg, 40% for 2 steps). 1H NMR (400 MHz, Acetone-d6) δ: 1.36 (s, 3H), 1.39 (s, 3H), 1.40 (s, 3H), 2.28 (m, 2H), 3.68 (m, 2H), 8.03 (dd, 1H, J1=6.57 Hz, J2=1.84 Hz), 8.14 (d, 1H, J=1.45 Hz), 8.24 (d, 1H, J=8.40 Hz).

Quelle