Preparation and Characterization of Bridged Naphthoxazinium Salts
摘要:
By condensation of bridged 4-arylazo-substituted 3-hydroxyanilines 18 and bridged or unbridged 4-arylazo-substituted 1-naphthylamines 19-23 with bridged 1-naphthylamines 15-17 and 3-aminophenols 14, respectively, in the presence of perchloric acid, bridged naphthoxazinium perchlorates 24-30 have been prepared. The spectral properties of the products have been compared with those of the bridged phenoxazinium salt 31 as well as with data for some unbridged analogues.
Hydrogenation of Quinaldine and Benzylic Aldehydes both Separately and Combined in a Tandem Hydrogenation–Reductive Alkylation of Quinaldine by Aldehydes with Iridium Benzoquinoline Catalysts
作者:Michael G. Manas、Jonathan Graeupner、Laura J. Allen、Graham E. Dobereiner、Kerry C. Rippy、Nilay Hazari、Robert H. Crabtree
DOI:10.1021/om400267n
日期:2013.8.26
under mild conditions. Our best catalyst is active in a significantly wider range of solvents than our previous systems. In the presence of a suitable base, the Ir(III) species is also able to hydrogenate the C═O bonds of aldehydes. When quinolines and aldehydes are present together, the Ir(III) complex catalyzes a tandem reaction in which the quinoline is first hydrogenated to a tetrahydroquinoline that
A General Catalyst Based on Cobalt Core–Shell Nanoparticles for the Hydrogenation of N‐Heteroarenes Including Pyridines
作者:Kathiravan Murugesan、Vishwas G. Chandrashekhar、Carsten Kreyenschulte、Matthias Beller、Rajenahally V. Jagadeesh
DOI:10.1002/anie.202004674
日期:2020.9.28
core–shell based nanoparticles prepared by template synthesis of cobalt‐pyromellitic acid on silica and subsequent pyrolysis. The optimal catalyst material allows for general and selective hydrogenation of pyridines, quinolines, and other heteroarenes including acridine, phenanthroline, naphthyridine, quinoxaline, imidazo[1,2‐a]pyridine, and indole under comparably mild reaction conditions. In addition
在此,我们报道了通过二氧化硅上钴均苯四酸的模板合成和随后的热解制备的特定二氧化硅负载的Co/Co 3 O 4核壳纳米粒子的合成。最佳的催化剂材料允许在相对温和的反应条件下对吡啶、喹啉和其他杂芳烃(包括吖啶、菲咯啉、萘啶、喹喔啉、咪唑并[1,2-a]吡啶和吲哚)进行全面和选择性氢化。此外,还展示了这些钴纳米颗粒的回收利用及其脱氢催化能力。
Synthesis and Characterization of Iron–Nitrogen-Doped Graphene/Core–Shell Catalysts: Efficient Oxidative Dehydrogenation of <i>N</i>-Heterocycles
and stable core-shell catalysts. In this respect, we present the synthesis and characterization of iron oxides surrounded by nitrogen-doped-graphene shells immobilized on carbon support (labeled FeOx@NGr-C). Active catalytic materials are obtained in a simple, scalable and two-step method via pyrolysis of iron acetate and phenanthroline and subsequent selective leaching. The optimized FeOx@NGr-C catalyst
The development of catalysts based on earth abundant metals in place of noble metals is becoming a central topic of catalysis. We herein report a cobalt/tetraphosphine complex catalyzed homogeneous hydrogenation of polar unsaturated compounds using an air- and moisture-stable and scalable precatalyst. By activation with potassium hydroxide, this cobalt system shows both high efficiency (up to 24000