69709-01-9Relevant academic research and scientific papers
Preparation method of D-HPPA
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Paragraph 0031; 0032, (2017/05/13)
The invention provides a novel preparation method of D-HPPA by using a novel catalyst. The method is simple and applicable to industrialization.
A periodic mesoporous hybrid material with a built-in palladium complex: An efficient catalyst for the Suzuki coupling and alcohol oxidation
Yang, Hengquan,Ma, Zhancheng,Qing, Yong,Xie, Guangyong,Gao, Jie,zhang, Li,Gao, Jinhua,du, Lin
experimental part, p. 312 - 321 (2010/08/20)
A new periodic mesoporous hybrid material with a built-in Pd-guanidine complex was synthesized in the presence of a structure-directing agent. The N2 sorption, XRD and TEM characterizations revealed that this hybrid material had a large surface area (>700 m2 g-1), a narrow pore size distribution (centered at 2.7 nm), and a periodic 2D-hexagonal structure. FT-IR, solid state NMR and XPS investigations confirmed that palladium-guanidine complex was covalently integrated with the solid material. The solid material exhibited high activity for the Suzuki coupling reaction of various aryl bromides in an aqueous ethanol solution under air. Furthermore, it was found that the solid material worked well for the aerobic oxidation of benzylic alcohols under ambient pressure of O2, affording over 99% selectivity. This catalyst could be reused 9 times without a decrease in selectivity. This study supplies a new periodic mesoporous hybrid material with a built-in active palladium sites, which may be applied to other catalytic reactions. Crown Copyright
Palladium-guanidine complex immobilized on SBA-16: A highly active and recyclable catalyst for Suzuki coupling and alcohol oxidation
Yang, Hengquan,Han, Xiaojing,Ma, Zhancheng,Wang, Runqin,Liu, Jing,Ji, Xiangfei
experimental part, p. 441 - 451 (2010/08/07)
By immobilizing a mixture of a palladium-guanidine complex and guanidine on the mesoporous cage-like material SBA-16 via a one-pot silylation, we have successfully prepared a new solid catalyst for Suzuki coupling and the aerobic oxidation of alcohols. The structure and composition of the solid catalyst were characterized with N2 sorption, XRD, TEM, FT-IR and solid state NMR. The coordination state of the palladium-guanidine complex supported on the solid catalyst was preliminarily investigated with XPS and UV-vis spectroscopy. This catalyst afforded fast conversions for the Suzuki coupling of various aryl bromides and arylboronic acids in a 50% aqueous ethanol solution at 50 °C even at loadings of 0.01-0.001 mol%, and the TOF (turn-over frequency) for the Suzuki coupling of bromobenzene and arylboronic acids could be up to 45700 h-1 under mild conditions. A satisfactory yield was obtained even after the catalyst was reused several times. The developed solid catalyst combined with the mild conditions investigated represents one of the most efficient heterogeneous systems for the Suzuki coupling of bromides. Furthermore, it was found that the solid catalyst could also work well for the aerobic oxidation of benzylic alcohols and cinnamyl alcohol, affording over 99% selectivity. The catalyst could be reused 15 times without a significant decrease in activity and selectivity.
