As such, chemoselectivity can be difficult to predict, but observing selective outcomes in cases where many reactions are plausible, is common. Examples include the selective organic reduction of the greater relative chemoselectivity of sodium borohydridereduction vs. lithium aluminium hydridereduction. In another example, the compound4-methoxyacetophenone is oxidized bybleach at the ketone group at high pH (forming the carboxylic acid) and oxidized byEAS (to the aryl chloride) at low pH