Hydroformylation of alkenes is one of the most important industrial processes for the production of value-added aldehydes. A new square-planar geometry rhodium(I) complex, Rh^I(CO)(terpyridine), has been synthesized and characterized using nuclear magnetic resonance (NMR), electrospray ionization mass spectrometry (ESI-MS), single-crystal X-ray diffraction (XRD), and scanning electron microscopy (SEM). This complex crystallizes in a self-replicating manner through Rh^I···Rh^I and π–π interactions at room temperature, allowing it to function as a carrier-free recyclable rhodium catalyst in the hydroformylation of various alkenes, which effectively addresses the challenge associated with the separation of catalysts from products. The unique packing model enables the Rh^I(CO)(terpyridine) complex to partially dissolve under hydroformylation conditions, thereby acting as a homogeneous catalyst. Furthermore, it maintains both consistent reactivity and structural integrity for cyclohexene hydroformylation reactions over 10 recycling runs under standard reaction conditions (40 bar, 100 °C, and 4 h). Additionally, Rh^I(CO)(terpyridine) integrated the advantages of homogeneous catalysis and heterogeneous separation, as demonstrated by its high reactivity and robust recyclability in the hydroformylation of long-chain C₆–C₁₈ alkenes, α-methylstyrene, and mixed octenes, highlighting its potential for industrial applications.

中文翻译：

---

用于烯烃加氢甲酰化的无载体可回收 Rh/特吡啶催化剂：均相催化和非均相分离


烯烃的加氢甲酰化是生产增值醛的最重要工业过程之一。已经合成了一种新的方形平面几何铑 （I） 配合物 Rh（CO）（三吡啶），并使用核磁共振 （NMR）、电喷雾电离质谱 （ESI-MS）、单晶 X 射线衍射 （XRD） 和扫描电子显微镜 （SEM） 进行了表征。这种复合物通过 Rh···在室温下 Rh 和 π-π 相互作用，使其能够在各种烯烃的加氢甲酰化中用作无载体的可回收铑催化剂，从而有效解决了与催化剂与产品分离相关的挑战。独特的堆积模型使 Rh（CO）（三吡啶）络合物能够在加氢甲酰化条件下部分溶解，从而充当均相催化剂。此外，在标准反应条件（40 bar、100 °C 和 4 h）下，它在环己烯加氢甲酰化反应中保持了 10 次循环运行，保持一致的反应性和结构完整性。此外，Rh（CO）（三吡啶）整合了均相催化和非均相分离的优势，其在长链 C_{6-C 18} 烯烃、α-甲基苯乙烯和混合辛烯的加氢甲酰化反应中的高反应性和强大的可回收性证明了这一点，突出了其在工业应用中的潜力。