Li Yan

N-Alkylation of amine with alcohol is an attractive route for synthesizing high-value amines. However, existing homogeneous and heterogeneous catalytic systems still suffer from limitations such as insufficient metal utilization, requirement for alkaline additives, poor recyclability, and limited intrinsic activity. Herein, we propose an alcohol-driven coordination tailoring strategy, in which the alcohol governs the transformation of pristine Ru1-3P sites into highly active Ru1-1P with a well-defined [RuH2Cl2(Ph-CHO)(PPh3)] configuration. In base-additive-free N-alkylation, the Ru1-1P/POPs catalyst delivers a TOF of 323 h–1 and an apparent activation energy of 70.1 kJ·mol–1, far outperforming the Ru1-3P/POPs (145 h–1, 103.3 kJ·mol–1) and surpassing most reported catalysts. Comprehensive characterization confirms that Ru remains atomically dispersed even after 10 cycles. Mechanistic studies reveal that different from traditional base-dependent pathways, this catalytic cycle follows a dihydride transfer mechanism. The unique Ru1-1P configuration significantly reduces the barrier of the rate-determining β-hydride elimination. This work provides a facile strategy for regulating single-atom coordination environments and deepens the understanding of structure-performance relationships at the molecular level.

The selective conversion of syngas to C ₄₊ long-chain alcohols holds significant industrial and scientific interest, but challenges in product selectivity and process efficiency remain. Here, we report a precisely catalytic strategy for C ₄₊ alcohol synthesis with a selectivity of 80% at 17% CO conversion. The reaction channel involves: (i) the development Cs ₂ O-Co ₂ C-Co catalysts, capable of catalyzing CO hydrogenation to long-chain oxygenates/olefins; and (ii) complete conversion to C ₄₊ alcohols is subsequently achieved on the single-Rh-site and Cu-ZrO ₂ interfaces by integrated cooperative catalysis. A comprehensive catalyst design and compatibility assessment of each catalytic module ensures optimal combinations, meanwhile effectively eliminates costly separation steps, and reduces CO ₂ selectivity down to 1%. The developed process achieves ultra-high carbon-efficiency (>95%) and improves oxygen-efficiency, effectively overcoming the key limitations of current syngas conversion technologies and thus representing a competitive and sustainable solution for producing high-value long-chain alcohols with a minimal carbon footprint.

Revealing key factors that modulate the regioselectivity in heterogeneous hydroformylation requires identifying and monitoring the dynamic evolution of the truly active center under real reaction conditions. However, unambiguous in situ characterizations are still lacking. Herein, we elaborately construct a series of Rh-POPs catalysts for propylene hydroformylation which exhibited tunable regioselectivity. Multi-technique approaches reveal the unique microenvironment of the diverse HRh(CO)(PPh₃-frame)₂ sites with distinct P-Rh-P bite angles ranging from 90° to 120° and 158° to 168°, respectively. In situ time-resolved XAFS, FT-IR, and quasi-in situ Solid-state NMR experiments combined with DFT calculations explain the dynamic evolution of the electronic and coordinate state of the distinct active sites induced by hemilabile PPh₃-frame ligands and further disclose the regulatory mechanism of regioselectivity. These state-of-the-art techniques and multiscale analysis advance the understanding of how hemilabile coordination influences regioselectivity and will provide a new thought to modulate the regioselectivity in future industrial processes.

An effective and feasible strategy to precisely regulate the framework of PPh ₃ based porous organic ligands (POLs) and the corresponding coordination microenvironment surrounding Rh was put forward by changing the position of cross-linkers.

Utilization of CO₂ for the production of fine chemicals has become a research hotspot for a long time. In order to make use of CO₂, we developed a highly efficient heterogeneous catalyst (denoted as Pd@POPs) for the N-formylation reaction of amine and CO₂ under mild conditions. The Pd catalyst was based on a porous organic polymer derived from the solvothermal polymerization of vinyl-functionalized PPh₃. A series of characterizations and comparative experiments demonstrated that the Pd@POPs catalyst has high BET (Brunauer-Emmett-Teller) surface areas, hierarchical pore structure, and uniform dispersion of Pd active sites resulting from the formation of strong coordination bonds between Pd species and P atoms in the porous organic polymer (POP) support. In addition to the excellent activity, the Pd@POPs catalyst shows good stability for the N-formylation reaction of amine and CO₂.