Alcohols are important compounds widely used in the food, fragrance, pharmaceutical and bulk/fine chemical industries. α,β-unsaturated alcohols can be produced via the hydrogenation of α,β-unsaturated aldehydes.  

However, during the hydrogenation process, many byproducts are obtained due to the competitive hydrogenation among the functional groups (such as C=C and C=O bonds) of α,β-unsaturated aldehydes, resulting in low yield of the α,β-unsaturated alcohols and high cost of purification. 

Recently, a research team led by Prof. WANG Guanghui from the Qingdao Institute of Bioenergy and Bioprocess Technology (QIBEBT) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. ZHANG Wenhua from University of Science and Technology of China (USTC), reported a new Ni₃Al₁-oxide hollow nanosphere (h-Ni₃Al₁-800) for α,β-unsaturated aldehydes conversion to α,β-unsaturated alcohols.

It is derived from Ni₃Al₁ layered double hydroxide grafted on hollow polymer spheres (HPS@Ni₃Al₁-LDH) by calcination at 800°C under air, where the selectivities towards unsaturated alcohols are always higher than 99 % at almost full conversions. 

"The hollow structure of the h-Ni₃Al₁-800 catalyst increases its surface area and porosity, leading to more available active sites. Moreover, the h-Ni₃Al₁-800 catalyst is very stable under reductive selective transfer hydrogenation (STH) conditions that can be recycled at least 12 times without loss in activity and selectivity," Prof. WANG said. 

"The Al dopant in the h-Ni₃Al₁-800 provides much stable Ni^δ+-type (2<δ<3) acid-base pairs and results in the high activity and excellent stability for STH reactions," said Prof. ZHANG.  

Besides, the h-Ni₃Al₁-800 is applicable for STH in a broad substrate scope with selectivities to corresponding unsaturated alcohols higher than 99 % at full conversion. 

This work proposes a novel catalyst for STH that is potential for industrial applications. 

The study was published on Oct. 9 in the Journal of Materials Chemistry A. It was supported by the National Natural Science Foundation of China and Natural Science Foundation of Shandong Province, China.