Borane → (3-Chloro-1-benzothien-2-yl)methanol

To a solution of 3-chloro-benzo[b]thiophene-2-carboxylic acid (3.5 g, 16.6 mmol) in THF (40 mL) at 0° C. was added drop-wise 1 M borane in THF (33 mL, 33.2 mmol) via a dropping funnel. The mixture was stirred at r.t overnight. The reaction was quenched with drop-wise addition of water (6 mL). Solvent was evaporated in vacuo and the residue was partitioned between sat. sodium carbonate and ethyl acetate. The aqueous phase was extracted with ethyl acetate (100 mL), the combined organic phases was washed with water (3×100 mL), dried and concentrated to give (3-chloro-benzo[b]thiophen-2-yl)-methanol as a light yellow solid (3.4 g, 103% crude yield); 1H NMR (DMSO-d6) δ 4.8 (d, J=5.8 Hz, 2H, CH2OH), 5.87 (t, J=5.8 Hz, 1H, CH2OH), 7.42-8.04 (m, 4H, Ar). The product was used in the next step without further purification.

1. customThe reaction was quenched with drop-wise addition of water (6 mL)
2. customSolvent was evaporated in vacuo
3. customthe residue was partitioned between sat. sodium carbonate and ethyl acetate
4. extractionThe aqueous phase was extracted with ethyl acetate (100 mL)
5. washthe combined organic phases was washed with water (3×100 mL)
6. customdried
7. concentrationconcentrated

ORD record

ord-9cd1f9f99aed42e9a35f0574ec3a16d0

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09181216B2