 Hence, this reaction is more useful for terminal alkynes than internal alkynes.The phenol can be liberated from the chromium complex by a mild oxidation, such as ceric ammonium nitrate or air oxidation.Since this reaction can quickly generate complex phenolic compounds, the Wulff–Dötz reaction has been used most often in the synthesis of natural products, especially Vitamins E and K. It is also applicable to the synthesis of polyphenolic compounds, such as calixarenes.