Chemical Properties
White solid
Uses
Reactant involved in: • ;Synthesis of aryl azides 1• ;Arylation of allylic chlorides2• ;Syntehsis of RNA conjugates3• ;Alkoxycarbonylation4• ;Synthesis of mTOR and PI3K inhibitors as antitumor agents5• ;Electrooxidative synthesis of biaryls6
Uses
4-Nitrobenzeneboronic acid pinacol ester is a reactant involved in synthesis of aryl azides, arylation of allylic chlorides, synthesis of RNA conjugates, alkoxycarbonylation, synthesis of mTOR and PI3K inhibitors as antitumor agents, electro oxidative synthesis of biaryls.
Synthesis Reference(s)
The Journal of Organic Chemistry, 60, p. 7508, 1995
DOI: 10.1021/jo00128a024
Synthesis
GENERAL PROCEDURE: To a solution of 4-nitroaniline (0.5 mmol, 1.0 eq.) in methanol (1.0 mL) was added hydrochloric acid (0.5 mL, 1.5 mmol, 3.0 eq.) followed by water (0.5 mL). The mixture was stirred for 2 minutes and then sodium nitrite solution (0.25 mL) was added. Sodium nitrite solution was prepared by dissolving 35 mg of sodium nitrite in water (0.25 mL). The reaction mixture was stirred at 0-5 °C for 30 min, followed by the addition of a methanol (1.0 mL) solution of pinacol ester of bisboronic acid (2,381 mg, 1.5 mmol, 3.0 equiv). Stirring was continued for 60 minutes. Upon completion of the reaction, water (10 mL) was added to the mixture, which was then extracted with dichloromethane (50 mL, 3 times). The organic layers were combined and washed with saturated sodium bicarbonate solution followed by drying with anhydrous sodium sulfate. After drying, the solvent was evaporated and the crude product was purified by fast chromatography.
References
[1] Synlett, 2014, vol. 25, # 11, p. 1577 - 1584
[2] Angewandte Chemie - International Edition, 2010, vol. 49, # 10, p. 1846 - 1849
[3] Tetrahedron Letters, 2016, vol. 57, # 14, p. 1551 - 1554
[4] Synlett, 2012, vol. 23, # 9, p. 1394 - 1396
