A General and Efficient Iron‐Catalyzed Benzylation of 1,3‐Dicarbonyl Compounds

Various CH‐acidic 1,3‐dicarbonyl compounds and methyl 3‐acetamidobut‐2‐enoate react with benzylic alcohols to give the corresponding 2‐benzylated products in good to excellent yield. Typically, reactions proceed under mild conditions (50–80 °C; air) in the presence of catalytic amounts of inexpensive iron chloride hexahydrate. The benzylation of 4‐hydroxycoumarin gives the pharmaceutically interesting 4‐hydroxy‐3‐(1‐phenylethyl)‐2 H ‐chromen‐2‐ones. As an example the anticoagulant Phenprocoumon is prepared in one step from commercially available substrates in 94 % yield.