Diisopropylamine → (2-Methoxypyridin-3-yl)boronic acid

Participants

Reaction Steps

A mixture of 2-methoxypyridine (23.2 g) and diisopropylamine (1.35 mL) in THF (223 mL) was added to (trimethylsilylmethyl)lithium (218 mL, 13.8 weight percent in hexanes) at −20° C. The lithiation was 84% complete after 7 hours. Tri-isopropylborate (40.8 g) was added at 20° C. over 40 minutes. The mixture was stirred overnight at ambient temperature. 5 percent NaOH (aq, 225 mL) was added. The aqueous layer was removed and brought to pH 5 by adding 10% HCl (aq). The resulting white precipitate was isolated by filtration. After drying, 22.23 g of 2-methoxypyridine-3-boronic acid was obtained (68% yield).

Provenance & Evidence