Potassium Hydroxide → (E)-5-Boronopent-4-enoic acid

Methyl (E)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pent-4-enoate (2.0 g, 8.33 mmol) was dissolved in MeOH (100 ml), a 0.8 M aqueous potassium hydroxide solution (52.1 ml, 41.6 mmol) was added and the mixture was stirred at room temperature overnight. MeOH was removed by concentration under reduced pressure, and 3 M hydrochloric acid was then added until the pH was 3. This aqueous solution was washed with tert-butyl methyl ether and then concentrated under reduced pressure. The resulting residue was purified by column chromatography (10 mM aqueous ammonium acetate solution:methanol). Obtained fractions were concentrated under reduced pressure, and the resulting solid was washed with tert-butyl methyl ether again to afford the title compound (674.6 mg, 56.3%).

1. customMeOH was removed by concentration under reduced pressure, and 3 M hydrochloric acid
2. additionwas then added until the pH was 3
3. washThis aqueous solution was washed with tert-butyl methyl ether
4. concentrationconcentrated under reduced pressure
5. customThe resulting residue was purified by column chromatography (10 mM aqueous ammonium acetate solution:methanol)
6. concentrationObtained fractions were concentrated under reduced pressure
7. washthe resulting solid was washed with tert-butyl methyl ether again

ORD record

ord-a2d3af3f914247a3964cdf4e6ab1ba34

Source dataset

uspto-grants-2016_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09409952B2