N-(2-(p-bromophenoxy)ethyl)pyrrolidine → 5-(Tert-butyl-dimethyl-silyloxy)-2-(7-(tert-butyl-dimethyl-silyloxy)-4-{1-hydroxy-1-[4-(2-pyrrolidin-1-yl-ethoxy)-phenyl]-ethyl}-2H-chromen-3-yl)phenol

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-[2-(4-bromophenoxy)-ethyl]-pyrrolidine (331 mg, 1.22 mmol) in THF (7.5 mL) at −78° C., was added n-butyl lithium (2.5 M in hexane, 478 μL, 1.19 mmol). The mixture was stirred at −78° C. for 0.5 hours. To this mixture was then added 2,8-bis-(tert-butyl-dimethyl-silyloxy)-11H-chromeno[4,3-c]chromen-5-one (153 mg, 0.30 mmol) in THF (3 mL), prepared as in Example 22. The reaction mixture was then stirred at −78° C. for 1.5 hours. To this mixture was added methyl magnesium bromide (3 M in diethyl ether, 1 mL, 2.99 mmol) at −78° C. and the reaction mixture stirred at room temperature overnight. The reaction was quenched with aqueous NH4Cl and extracted with ethyl acetate. The organic layer was washed with brine and dried over MgSO4. The solvent was evaporated to yield the crude product as a yellow oil. The crude product was carried to the next step without further purification.

Provenance & Evidence