Methyl (trimethylsilyl)acetate → Methyl 3-(3-(tert-butyldimethylsilyloxy)-2-fluorophenyl)-4-cyclopropylbut-2-enoate

Participants

Reaction Conditions

Reaction Steps

A 25 mL round bottom flask was cooled to −78° C. under N2 and charged with THF (2 mL) and lithium diisopropylamide (2.0 M in heptane/THF/ethylbenzene) (2.1 mL, 4.1 mmol) (available from Aldrich). To the cold, brown solution was added methyl (trimethylsilyl)acetate (0.61 mL, 3.7 mmol) (available from Aldrich) dropwise. The orange mixture was stirred for 15 minutes, and to it was added a solution of 84.C (0.46 g, 1.5 mmol) in THF (2 mL) dropwise. The mixture was stirred for 30 minutes at −78° C., the cooling bath was removed, and the mixture was stirred for 30 minutes at ambient temperature. The reaction was quenched with saturated aqueous NH4Cl and diluted with EtOAc. The organic phase was washed with water, 1 N HCl and brine. The organic phase was then dried (MgSO4) and concentrated. The residue was purified by silica gel flash chromatography (0-2% EtOAc/hexane) to afford 84.D (mixture of geometric isomers) (0.44 g, 81% yield) as a yellow oil.

Provenance & Evidence