反应详情

To a solution of tributyl tin hydride (8.5 mL, 29.23 mmol, Aldrich) in THF (50 mL) was added LDA (2.0 M) (THF/heptane/ethyl benzene) (18.3 mL, 29.23 mmol, Aldrich) at 0° C. and the mixture was stirred for 10 min at RT. To the mixture at 0-5° C. was added 6-chloro-N-isopropylpyrazin-2-amine (2.5 g, 14.61 mmol) and the mixture was stirred for an additional 3 h at RT. The reaction was quenched with 10% aq KF (25 mL) and extracted with EtOAc (2×25 mL). The combined organic layers were dried over anhydrous Na2SO4 and concentrated. The residue was further purified with basic alumina column chromatography (eluent: 10% EtOAc in petroleum ether) to give N-isopropyl-6-(tributylstannyl)pyrazin-2-amine (2 g, 26.5%) as a colorless liquid. MS (ESI, pos. ion) m/z: 428.2 (M+1); 1H-NMR (400 MHz, CDCl3): δ 7.77 (s, 1H), 7.64 (s, 1H), 4.28-4.23 (m, 1H), 4.09-3.98 (m, 1H), 1.63-1.54 (m, 7H), 1.39-1.23 (m, 14H), 1.12-1.08 (m, 6H), 0.91-0.88 (q, 6H).

1. stirringthe mixture was stirred for an additional 3 h at RT
2. customThe reaction was quenched with 10% aq KF (25 mL)
3. extractionextracted with EtOAc (2×25 mL)
4. dry with materialThe combined organic layers were dried over anhydrous Na2SO4
5. concentrationconcentrated
6. customThe residue was further purified with basic alumina column chromatography (eluent: 10% EtOAc in petroleum ether)