1,10-菲啰啉修饰Cu/Al_(2)O_(3)催化肉桂醛羰基高效选择性加氢

N-Ligand Regulated Heterogenous Copper Catalyst for Selective Hydrogenation of Cinnamaldehyde

肉桂醛作为α,β-不饱和醛的代表性物质,其羰基选择性加氢的高效催化剂设计还存在一定挑战.经过1,10-菲啰啉(L1)修饰制备的Cu催化剂(Cu/Al_(2)O_(3)-L1),可以在肉桂醛几乎完全转化的情况下实现>95%的肉桂醇选择性.表征和DFT结果表明,1,10-菲啰啉的空间位阻限制了肉桂醛的平面吸附,提高了肉桂醇的选择性,同时其与Cu的相互作用降低了H2的解离能,提高了催化剂的活性.这项工作强调了含N-配体在催化剂表面修饰中的重要性,并为进一步合理设计高选择性加氢催化剂提供了一些借鉴.

Cinnamaldehyde(CAL)as a representative substance ofα,β-unsaturated aldehydes,its selective hydrogenation is an extremely important transformation,while developing efficient catalysts with desirable selectivity to highly value-added products is challenging.Herein,we report a supported nano-Cu catalyst modified by 1,10-phenathroline(Cu/Al_(2)O_(3)-L1),which achieved an extraordinary cinnamylalcohol(COL)selectivity(95%)with almost complete transformation of CAL.The characterization and DFT showed that the excellent results were attributed to the interaction between Cu and 1,10-phenathroline and steric hindrance of L1 which constrained the flat adsorption configuration of CAL and improves the selectivity of COL.In addition,the new surface of catalyst strengthens the interaction between Cu and H2,which reduced the dissociation energy of H2,benefits to improve the activity of catalyst.This work highlighting the importance of precisely controlled catalyst surface with N-Ligand and provides the possibility to break the trade-off between activity and selectivity for hydrogenation of chemicals containing variety of reducing groups.