Water was added, and the product was extracted with DCM. The combined organic layers were washed with brine, dried over Na2SO4, and concentrated in vacuo. The crude product was purified by flash chromatography on a silica gel column (eluent 100% EtOAc) to give the product as a white solid (89 mg, 63% over 2 steps). Rf = 0.17 (eluent 100% EtOAc); General procedure for the deprotection of N-Boc protected boronic esters. The boronic ester (1 eq) was dissolved in DCM (0.1 M), and the solution was cooled to -78℃. BCl3 (1M in DCM, 3.5 eq) was added dropwise, and the solution was stirred at -78℃ for 1h. MeOH (12 eq) was added slowly at -78℃. The solution was concentrated in vacuo, and the residue was dissolved in DCM. The product was extracted with water, and the combined aqueous phases were washed with Et2O and concentrated in vacuo to give the product as a solid with no further purification necessary. NMR spectra, dose-response curves for each compound (PDF)