反应详情

6-Bromopyridine-3-carboxylic acid (122 mg, 0.82 mmol, 1.3 eq) was dissolved in DCM (5 mL) and oxalyl chloride (72 μL, 0.82 mmol, 1.3 eq) was added dropwise followed by a drop of DMF. The reaction was stirred for 1 h at ambient temperature, then N,N-diethylethanamine (1 mL, 1.89 mmol, 3 eq) was added followed by tert-butyl 5-amino-3-[2-(3-methoxyphenyl)ethyl]pyrazole-1-carboxylate (200 mg, 0.63 mmol, 1 eq). The reaction was stirred for 2 h, then diluted with DCM and washed with water, brine, dried (MgSO4), filtered and evaporated to give the crude Boc-protected compound as a yellow gum. The gum was dissolved in 2-propanol (5 mL) and a solution of 6M HCl in 2-propanol (4 mL) was added. The solution was stirred at ambient temperature overnight and was then evaporated to dryness and loaded onto a SCX-2 column. The column was washed with methanol and the product eluted with 2N ammonia in methanol to give an orange solid. Trituration with a small volume of methanol gave 6-chloro-N-[5-[2-(3-methoxyphenyl)ethyl]-2H-pyrazol-3-yl]pyridine-3-carboxamide (39 mg, 17%) as a white solid; 1H NMR (400.13 MHz, DMSO) δ 2.89 (4H, s), 3.74 (3H, s), 6.46 (1H, s), 6.75 (1H, m), 6.81 (2H, m), 7.20 (1H, t), 7.65 (1H, d), 8.35 (1H, m), 8.95 (1H, d), 10.99 (1H, s), 12.23 (1H, s) MS m/z 357 (MH+)

1. stirringThe reaction was stirred for 2 h
2. washwashed with water, brine
3. dry with materialdried (MgSO4)
4. filtrationfiltered
5. customevaporated
6. customto give the crude Boc-protected compound as a yellow gum
7. stirringThe solution was stirred at ambient temperature overnight
8. customwas then evaporated to dryness
9. washThe column was washed with methanol
10. washthe product eluted with 2N ammonia in methanol
11. customto give an orange solid