Abstract
Selective hydrogenations of alkynes are a class of essential reactions in organic synthesis chemistry. Particularly, the selective hydrogenation of acetylene to ethylene is a key step in the production of polymers. Here we have successfully performed selective hydrogenation of acetylene to ethylene in N,N-dimethylformamide by iron-based nanoparticles, especially by Pd-Fe bimetallic NPs. NaBH4 as a hydrogen source can significantly increase the catalytic performances of nanocatalysts for acetylene hydrogenation. More importantly, the reaction is carried out at exceptionally mild temperature and under additive-free conditions with high ethylene selectivity (>90%) as well as excellent catalyst reactivity and stability. By this strategy, we could attain a catalytic activity higher by a factor of 2.2 orders of magnitude than that of the currently used industrial method. This approach may open a new way to perform selective acetylene and other alkynes hydrogenation under mild conditions, and offer another promising application for zerovalent iron reduction method.