反应详情

A mixture of 5-bromo-2,3-dichlorobenzaldehyde from the previous step (1 eq.), cyclopropylamine (1 eq.) and sodium cyanoborohydride (1.5 eq.) were combined in MeOH (0.2 M). At 0° C., acetic acid (3 eq.) was added dropwise and the reaction mixture was slowly warmed to RT over 16 h. The reaction mixture was then diluted with ether and quenched with 1N aq. NaHCO3. The aqueous layer was separated and back-extracted with ether. The combined organic extracts were then washed with brine, dried over MgSO4, filtered and the filtrate concentrated in vacuo. Purification of the crude product thus obtained by way of flash chromatography (SiO2, Hex→80:20 (v/v) Hex:EtOAc) afforded the title compound as a colorless oil.

1. customquenched with 1N aq. NaHCO3
2. customThe aqueous layer was separated
3. extractionback-extracted with ether
4. washThe combined organic extracts were then washed with brine
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. concentrationthe filtrate concentrated in vacuo
8. customPurification of the crude product
9. customthus obtained by way of flash chromatography (SiO2, Hex→80:20 (v/v) Hex:EtOAc)