Selective iron-catalyzed transfer hydrogenation of terminal alkynes

A novel iron-catalyzed transfer hydrogenation of alkynes to the corresponding alkenes applying formic acid as a hydrogen donor is reported. An in situ combination of Fe(BF4)(2)center dot 6H(2)O and tetraphos allows for highly selective hydrogenation of a broad range of aromatic and aliphatic alkynes tolerating different functional groups.