反应详情

A solution of LiOH (67 mg, 2.8 mmol) in H2O (1 ml) was added to a stirred solution of methyl {(2S,4R)-1-[(1S)-4-methyl-1-(3-methylbutyl)pent-4-en-2-yn-1-yl]-2-[4-(trifluoromethyl)phenyl]piperidin-4-yl}acetate (Step 1, 250 mg, 0.56 mmol) in THF (2 ml) at RT. The mixture was stirred at RT for 18 hrs, then at 60° C. for 3 hrs. After cooling to RT 2N HCl was added and the THF was removed in vacuo. The residue was partitioned between CH2Cl2/H2O. The pH of the aqueous layer was adjusted to ˜pH7 with saturated aqueous NaHCO3. The aqueous layer was extracted with CH2Cl2 (×3). The combined extracts were dried (Na2SO4) filtered and evaporated. The residue was purified by chromatography (silica, 4% MeOH/CH2Cl2) to give the acid (228 mg) as a colourless foam. 1H NMR (500 MHz, CD3OD): δ 0.83 (6H, d, J 6.6), 1.12-1.20 (2H, m), 1.33-1.43 (3H, m), 1.58 (2H, q, J 7.8), 1.80 (1H, dd, J 2.8, 12.8), 1.85-1.91 (5H, s), 2.18-2.26 (2H, m), 2.48 (1H, t, J 11.1), 2.98-3.04 (1H, m), 3.16 (1H, t, J 7.6), 3.55 (1H, dd, J 2.5, 11.3), 5.21 (1H, s), 5.24 (1H, s), 7.53 (2H, d, J 7.6), 7.62 (2H, d, J 8.2); M/Z (ES+) 436 (MH+).

1. waitat 60° C. for 3 hrs
2. additionwas added
3. customthe THF was removed in vacuo
4. customThe residue was partitioned between CH2Cl2/H2O
5. extractionThe aqueous layer was extracted with CH2Cl2 (×3)
6. dry with materialThe combined extracts were dried (Na2SO4)
7. filtrationfiltered
8. customevaporated
9. customThe residue was purified by chromatography (silica, 4% MeOH/CH2Cl2)