1627917-17-2

B-benzo[b]naphtho[2,3-d]furan-2-yl-boronic acid can be used as organic synthesis intermediate and pharmaceutical intermediate, mainly used in laboratory research and development process and chemical production process.

12.6g of intermediate (A) and 500 mL of tetrahydrofuran (dehydrated) were put in a flask, and the resultant was cooled to -78°C. 28 mL of n-BuLi (1.60M in hexane) was added, and stirring was conducted for 2 hours while elevating the temperature to 0°C. Then, the solution was again cooled to -78°C, and 11.6g of B(OMe) 3 was added. After stirring at 10 minutes at -78°C, stirring was further conducted for 5 hours while gradually elevating the temperature to room temperature.  After completion of the reaction, 1 N HCl aq. (100 mL) was added, and the reaction solution was stirred at room temperature for 1 hour. Then, the solution was transferred to a separating funnel, and extracted with ethyl acetate. This solution was dried with MgSO 4, concentrated and washed with hexane, whereby 7.2g (yield: 65%) of white solids of intermediate (B) were obtained.