4-Bromo-2-fluorobenzaldehyde → 4-Bromo-1-ethenyl-2-fluorobenzene

Participants

Reaction Conditions

Reaction Steps

To a suspension of methyltriphenylphosphonium bromide (1.1 eq) in tetrahydrofuran (0.13M) at −78° C., was added n-butyllithium (2.5M in hexanes, 1.1 eq) dropwise over 20 min. The reaction mixture was stirred at −78° C. for 15 min, warm to 0° C., stirred for 15 min and cooled back to −78° C. A solution of 4-bromo-2-fluoro-benzaldehyde (1 eq) in 100 mL THF was added dropwise over 30 min. Final mixture was allowed to warm slowly to rt and stirred for 1 h. The resulting mixture was quenched with a saturated NH4Cl solution and diluted with 2 volume of hexane. The organic extract was washed with brine, dried over MgSO4, filtered and concentrated. The residue was diluted with Hexane/EtOAc (9:1) and filtered on a pad of Silica gel. The fractions were combined and concentrated to afford the desired material.

Provenance & Evidence