Nitrogen → HCID 57755080, compound

Participants

Reaction Conditions

Reaction Steps

Synthesis of 4-(phenylethynyl)phenyl boronic acid (JACS, 2004, 126, 5798): In a flame-dried flask, 4-(phenylethynyl)-1-bromobenzene (15.0 g, 58.4 mmol) was dissolved in dry THF (225 mL). The solution was treated with 3 cycles of evacuation and refilling with N2, then chilled to −78° C. in a dry ice/acetone bath. To the stirred solution was added a solution of n-butyllithium in hexanes (1.6 M, 40 mL, 1.1 eq) by syringe over the course of 10 minutes. The resulting solution was stirred for an additional 30 minutes before trimethylborate (9.77 mL, 9.1 g, 1.5 eq) was added slowly over 15 minutes. After stirring for an additional 15 minutes, the cooling bath was removed and the solution was allowed to warm to room temperature and stir for 16 h. At this time, 2 M HCl (aqueous) (375 mL) was added, and the biphasic system was stirred vigorously for 2 hours. Ethyl acetate was added, and the organic layer was separated, dried (MgSO4), filtered and evaporated. Methylene chloride (100 mL) was added to the solid residue, which was crushed and mixed into a paste, then filtered and washed with additional portions of methylene chloride to give 8.5 g of the title compound as a white powder.

Provenance & Evidence