Recently, i have prepared a solution containing 10% NaOH in a mixture of THF/MeOH/H2O 2:1:1. This solution was prepared for hydrolysis of benzoyl protecting group. After starting my reaction, i went home without trashing the excess solution. The next morning, the solution had turned yellow. The color disappeared after neutralisation with HCl 10%. Do someone know what the cause of that color?
Thank you in advance