反应详情

n-BiLi (12.3 ml of 1.6 M in hexane, 20 mmol) is added dropwise to a solution of 4-bromo-1-chloro-3-methyl-isoquinoline (4.6 g, 18 mmol) in THF (80 ml) at −78° C. and the mixture is stirred for 40 min. DMF (4.2 ml, 54 mmol) is then added slowly. The cold bath is removed, and stirring is continued for 15 min. The mixture is acidified with 1N—HCl to pH 2 and extracted with ether. The combined extracts are dried over Na2SO4 and concentrated in vacuo. The residue is chromatographed on silica gel to give 3.0 g of 1-chloro-3-methyl-isoquinoline-4-carbaldehyde. 1H NMR (CDCl3) 10.9 (s, 1H), 9.06 (d, 1H), 8.40 (d, 1H), 7.88 (t, 1H), 7.70 (t, 1H), 2.99 (s, 3H).

1. customThe cold bath is removed
2. stirringstirring
3. waitis continued for 15 min
4. extractionextracted with ether
5. dry with materialThe combined extracts are dried over Na2SO4
6. concentrationconcentrated in vacuo
7. customThe residue is chromatographed on silica gel