Triisopropyl borate → 3-Vinylbenzo[c][1,2]oxaborol-1(3H)-ol

To a suspension of NaH (1.23 g, 28.2 mmol, 1.2 equiv., 60% content) in THF (10 mL) was added a solution of 1-(2-bromophenyl)prop-2-en-1-ol (5.0 g, 23.5 mmol, 1.0 eq) in THF (10 mL) dropwise at 0° C. The mixture was stirred for 1 h, then, cooled to −70° C. n-BuLi (11.3 mL, 28.2 mmol, 1.2 eq., 2.5M in THF) was added. The mixture was stirred for 1 h, then, triisopropyl borate (5.3 g, 28.2 mmol, 1.2 equiv.) was added. The mixture was stirred for 5 h, then, quenched with 2N H2SO4. The mixture was partitioned between brine and ethylacetate. The organic layer was washed over brine, dried over Na2SO4, filtered and concentrated. The residue was purified by column chromatography to yield 3-vinylbenzo[c][1,2]oxaborol-1(3H)-ol (2.2 g, 57%). LC-MS (m/z)=158.9, 160.9 [M+H]+.

1. additionwas added
2. stirringThe mixture was stirred for 1 h
3. stirringThe mixture was stirred for 5 h
4. customquenched with 2N H2SO4
5. customThe mixture was partitioned between brine and ethylacetate
6. washThe organic layer was washed over brine
7. dry with materialdried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated
10. customThe residue was purified by column chromatography

ORD record

ord-c5e79669d2a046c79f107be3e1aa4d28

Source dataset

uspto-grants-2016_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09422271B2