A universal atomically dispersed cobalt catalyst for alkylation of ketones alcohols and lignin-derived compounds
Zhuang Ma1, Binyu Zhang2,3, Yanbin Cui3
1Leibniz-Institut für Katalyse e.V., Rostock, Germany. zhuangmachem@hotmail.com.
Abstract:
Catalytic carbon-carbon bond-forming reactions provide the basis for synthetic organic chemistry. To move towards a circular carbon economy, it is imperative to efficiently convert sustainable and inexpensive starting materials, e.g. broadly available renewable feedstocks, in an economically viable and practical manner. In this work , we present a method for the atom-efficient and "waste-free" construction of C-C bonds in ketones with alcohols, including lignin-derived compounds. The broad applicability of this protocol is based on the development of a novel heterogeneous cobalt-based single atom catalyst, which is produced by subjecting a cobalt-poly(p-phenylenediamine)-silica template to pyrolysis and subsequently removing residual silica. The most effective catalyst material consists of isolated cobalt atoms with Co-N4 active sites dispersed on mesoporous carbon. The resulting material is both highly stable and reusable. The presented method facilitates the general and selective C-alkylation of aromatic, heterocyclic, and aliphatic ketones, as well as secondary alcohols. Applications include the functionalization of bioactive molecules and the preparation of pharmaceutical drugs and valuable methylated compounds. The value of the cobalt-single atom catalyst is further demonstrated in the industrially relevant C-alkylation of KA oil.
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