反应详情

To a stirring solution of 2-tert-butyl-5-(3,3-dimethoxy-cyclobutyl)-2H-pyrazol-3-ylamine (5.0 g, 19.7 mmol) in EtOAc (40 mL) was added triethylamine (27 mL, 197 mmol), TFA (2.3 mL, 29.6 mmol), followed by a solution of 1-propanephosphonic acid cyclic anhydride (25 mL, 50 wt % sol. in EtOAc, 39.4 mmol). After 72 hr, the reaction was diluted with EtOAc and washed with aqueous NaOH (1 N). The organic layer was dried over MgSO4, filtered, and concentrated under reduced pressure. Purification of this material was accomplished by MPLC, using a Biotage® column (35 L), eluting with 25% EtOAc/hexanes. The product-containing fractions were collected and concentrated to yield the title compound (4.1 g, 60% yield) as a colorless oil. 400 MHz 1H NMR (CDCl3) d 8.00 (bs, 1H), 6.26 (s, 1H), 3.22 (dddd, J=8.7, 8.7, 8.7, 8.7, Hz, 1H), 3.18 (s, 3H), 3.15 (s, 3H), 2.61-2.55 (m, 2H), 2.25-2.19 (m, 2H), 1.59 (s, 9H). LRMS m/z (APCI+) 350 (M+1).

1. washwashed with aqueous NaOH (1 N)
2. dry with materialThe organic layer was dried over MgSO4
3. filtrationfiltered
4. concentrationconcentrated under reduced pressure
5. customPurification of this material
6. washeluting with 25% EtOAc/hexanes
7. customThe product-containing fractions were collected
8. concentrationconcentrated