Atomically dispersed Zn sites on N-doped carbon boosted transesterification of symmetrical organic carbonates with biomass-derived alcohols

Transesterification of symmetrical organic carbonates with alcohols to access the unsymmetrical ones is a highly attractive strategy for upgrading biomass-derived alcohols. Robust, facile-prepared, and cost-effective catalytic materials remain highly desirable for this route. Herein, we designed several Zn-based catalysts (denoted as Zn@C-T, where T represented the pyrolysis temperature) by the pyrolysis of Zn-based coordination polymer at different temperatures. Very interestingly, the prepared Zn@C-900 could efficiently catalyze the transesterification of diethyl carbonate (DEC) with various biomass-derived alcohols to synthesize the corresponding unsymmetrical organic carbonates with high yields (>95 %), resulting from the atomically dispersed ZnN_x sites on the N-doped carbon. Notably, good catalytic activity could be obtained at a low temperature of 80 °C, representing the major breakthrough. Detailed investigations indicated that the excellent performance of Zn@C-900 originated mainly from the synergistic effect of Zn (to activate DEC) and N (to activate the alcohols) in the ZnN_x sites. This work provided a promising efficient catalyst for low-temperature production of unsymmetrical organic carbonates via transesterification of DEC.