Hydrochloric Acid → (4-Cyclopropoxyphenyl)boronic acid

Participants

Reaction Steps

To a solution of 4-bromo-4-cyclopropoxybenzene (5.0 g, 23.4 mmol, see Example 39(c)) in THF (80 mL) at −78° C. was added n-BuLi (2.5 M solution in hexane; 9.76 mL, 24.4 mmol) over 17 min. After 40 min, B(OEt)3 (5.9 mL, 34.3 mmol) was added and the reaction was warmed to room temperature and stirred at ambient temperature for 18 h. After re-cooling to 0° C., HCl (1M solution; 70 mL, aq.) was added. After 30 min the mixture was extracted with t-BuOMe (3×50 mL), the combined organic extracts were washed with brine, dried (Na2SO4) and concentrated. The residue was washed with light petrol and filtered yielding the sub-title compound (1.5 g, 34%).

Provenance & Evidence