Methanol → 1-(Triisopropylsilyl)pyrrole-3-boronic acid

Temperature

-78 °C

To a solution of 3-bromo-1-(triisopropylsilyl)-1H-pyrrole (0.691 g, 2.28 mmol) in THF (10 mL) at −78° C. was added t-butyllithium (2.83 mL, 4.80 mmol of 1.7M solution in heptane). The solution was stirred at −78° C. for 45 min, then trimethylborate (2.38 g, 22.8 mmol) was added and stirred at −78° C. for 20 min. The reaction mixture was allowed to warm to rt and then cooled again to −78° C. before methanol:water (V:V=1:1, 0.9 mL) was added and the solution allowed warm to rt. The reaction mixture was quenched with brine (10 mL) and extracted with EtOAc (3×25 mL). The combined organic phase was washed with brine, dried over Na2SO4 and concentrated in vacuo to give crude 1-(triisopropylsilyl)-1H-pyrrol-3-ylboronic acid which was used without further purification.

1. stirringstirred at −78° C. for 20 min
2. temperatureto warm to rt
3. temperaturethe solution allowed warm to rt
4. customThe reaction mixture was quenched with brine (10 mL)
5. extractionextracted with EtOAc (3×25 mL)
6. washThe combined organic phase was washed with brine
7. dry with materialdried over Na2SO4
8. concentrationconcentrated in vacuo

ORD record

ord-ed39a80758d44980a7f8bada2feeb005

Source dataset

uspto-grants-2008_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07371767B2