反应详情

To a solution of 26.4 g (83.8 mmol) of dimethyl 2-cyano-3-(2,4,5-trifluorophenyl)pentanedioate from Step B in 120 mL of methanol was added 5.0 g (22 mmol) of platinum(IV) oxide. The reaction mixture was shaken under 50 psi of hydrogen for 16 h at which point the reaction was diluted with 400 mL of a 3:1 mixture of chloroform and 2-propanol to dissolve the desired white solid, and filtered through a pad of Celite. The filter cake was successively washed with three portions of 400 mL of the above solvent mixture. The combined filtrate and washings were concentrated and then taken up in 150 mL of ethyl acetate, stirred for 5 min, then 150 mL of hexanes was added and stirred for 5 min. The white precipitate was filtered to afford the title compound which was used without further purification. LC/MS 288.3 (M+1).

1. dissolutionto dissolve the desired white solid
2. filtrationfiltered through a pad of Celite
3. washThe filter cake was successively washed with three portions of 400 mL of the above solvent mixture
4. concentrationThe combined filtrate and washings were concentrated
5. addition150 mL of hexanes was added
6. stirringstirred for 5 min
7. filtrationThe white precipitate was filtered