The epoxidation of butadiene to butadiene monoxide(BMO) is an attractive commercial process because BMO is an important intermediate for the production of many oxygenated heterocyclic compounds [1].Especially,BMO is readily used to prepare vinyl ethylene carbonate(VEC) which can largely improve the performance of the secondary battery as an additive.A μ-oxo-iron(Ⅲ) dimer,[((phen)2(H2O)Fem)2(μt-O)](ClO4)4 is an efficient catalyst for synthesis of BMO from 1,3-butadiene using peracetic acid as the oxidant [2].Low loading of this catalyst is sufficient for high conversion and product yield.The product yield and conversion were analysed by gas chromatography (GC) using the internal standard integration.Typically,with a loading of 0.25% catalyst,the product yield and conversion were more than 70% and 98% at-30℃ for 30 min.After removing the iron complex by workup,isolated sample product can be obtained from fractional distillation [3].The structure of an isolated sample product was assigned through a combination of H-NMR and GC/MS.The results show that the product with 98% purity can be obtained via this separation method.