反应详情

6-Bromo-1,1-dimethyl-indan (prepared by using a well-known method: patent application WO2005066115) 4a (4.32 g, 19.27 mmol) was dissolved in 40 mL of tetrahydrofuran and then butyllithium (15.67 mL, 1.6 M, 25.05 mmol) was added dropwise at −78° C. After the reaction mixture was reacted for 40 minutes, a solution of di-tert-butyl azodicarboxylate (5.32 g, 23.12 mmol) in 30 mL of tetrahydrofuran was then added. The reaction mixture was reacted for another 3 hours at −78° C. The reaction mixture was added with 5 mL of methanol, then warmed up to room temperature and filtered by silica gel. The filtrate was concentrated under reduced pressure and the resulting residue was purified by silica gel column chromatography to obtain the title compound di-tert-butyl 1-(3,3-dimethyl-1H-inden-5-yl)hydrazine-1,2-dicarboxylate 4b (2.70 g, yield 37.2%) as a yellow solid.

1. customAfter the reaction mixture was reacted for 40 minutes
2. customThe reaction mixture was reacted for another 3 hours at −78° C
3. filtrationfiltered by silica gel
4. concentrationThe filtrate was concentrated under reduced pressure
5. customthe resulting residue was purified by silica gel column chromatography