反应详情

The title compound was prepared according to general procedure B described in connection with Scheme 2. 1-tert-Butyl 3-methyl 3-(methoxymethyl)pyrrolidine-1,3-dicarboxylate (4.5 g, 16.5 mmol) was dissolved in 30 mL of MeOH and a solution LiOH (0.79 g, 33 mmol) in 20 mL was added. The reaction mixture was microwaved at 130° C. for 25 min in 5 vials. The methanol was evaporated and the residue was acidified to pH 1-2 with KHSO4 solid. The acid was extracted with EtOAc (3×50 mL). The combined organic fractions were washed with 1N KHSO4 and with brine and then dried over Na2SO4. The solvent was evaporated to give 7.09 g of the desired acid (91% crude yield). 1H NMR (400 MHz, CDCl3): δ 10.70 (bs, 1H), 3.76 (d, 1H), 3.62-3.41 (m, 5H), 3.35 (s, 3H), 2.34-2.25 (m, 1H), 1.98-1.93 (m, 1H), 1.45 (s, 9H); MS (ESI) m/z: Calculated for C12H21NO5: 259.1. found: 260 (M+1)+.

1. customThe reaction mixture was microwaved at 130° C. for 25 min in 5 vials
2. customThe methanol was evaporated
3. extractionThe acid was extracted with EtOAc (3×50 mL)
4. washThe combined organic fractions were washed with 1N KHSO4 and with brine
5. dry with materialdried over Na2SO4
6. customThe solvent was evaporated