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-ab839398eceb4c07b67ed0a6fd9a2a8a

Source dataset

uspto-grants-2012_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08153659B2