Dimethylformamide → 3-{[tert-Butyl(dimethyl)silyl]oxy}-5-ethyl-2-fluorobenzaldehyde

Participants

Reaction Conditions

Reaction Steps

To a solution of Intermediate 188.2 (7.50 g, 29.5 mmol) and PMDTA (6.5 mL, 31.1 mmol) in 30 mL THF at −78° C., was added BuLi (1.4 M in hexanes, 23.2 mL, 44.3 mmol). The thick slurry was stirred at −40° C. for 30 min, was recooled to −70° C. DMF (4.57 mL, 59 mmol) was added. The yellow solution was removed from the cooling bath and allowed to warm to rt and stirred 1 h. The reaction was quenched with sat. NH4Cl, then was diluted with hexanes. The organic phase was washed with H2O (3×) and brine, dried (Na2SO4), filtered through 2″ silica gel (eluting with 5% EtOAc/hexanes), then concentrated to afford 8.03 g of Intermediate 188.3 as a pale yellow oil.

Provenance & Evidence