10.1021/om900925b
The research focuses on the synthesis, coordination chemistry, and catalytic properties of the first 1,2-bis(diphenylphosphino)-1,2-diphenylhydrazine (PNNP) ligand and its complexes with Ni(II), Pd(II), and Pt(II). The ligand was synthesized by reacting chlorodiphenylphosphine with dilithiohydrazobenzene, and its complexes were formed by treating the ligand with NiCl2(DME), PdCl2(PhCN)2, and PtCl2(COD). The molecular structures of the ligand and its complexes were determined using X-ray diffraction. The catalytic activity of the ligand and its Ni(II) complex was evaluated in the oligo- and polymerization of ethylene using methylaluminoxane (MAO) and triethylaluminium (TEA) as cocatalysts. The experiments involved the preparation of the ligand and its complexes, followed by their application in catalytic reactions under controlled conditions. The products were analyzed using techniques such as gas chromatography, NMR spectroscopy, and melting point measurements.
10.1039/b820798b
The study focuses on the synthesis and application of half-sandwich chromium(III) complexes bearing β-ketoiminato and β-diketiminate ligands as catalysts for ethylene polymerization in the presence of triethylaluminium (AlEt3). These complexes were designed to produce high molecular weight polyethylene with good catalytic activity under mild conditions. The chemicals used in the study include chromium-based complexes with various β-ketoiminato and β-diketiminate ligands, triethylaluminium as a co-catalyst, and ethylene as the substrate for polymerization. The purpose of these chemicals was to create a catalyst system that could efficiently polymerize ethylene into high molecular weight polyethylene, offering an alternative to traditional metallocene catalysts and potentially leading to new insights into the mechanism of olefin polymerization.
10.1021/jo981075c
The research focuses on the synthesis of enantiopure highly substituted trans-8a-hydroxydecahydroisoquinolines, which are significant components of over 500 alkaloids and hold synthetic interest due to their potential biological activity. The study employs a diastereoselective approach involving a sequential intramolecular Diels-Alder (IMDA) reaction and oxanorbornene nucleophilic ring opening, utilizing chiral perhydrobenzoxazines derived from (-)-8-aminomenthol as a chirality inductor. Key chemicals in the process include 2-furaldehyde, (-)-8-((3′-butenyl)amino)menthol, aluminum hydride, pyridinium chlorochromate (PCC), potassium hydroxide, and triethylaluminum, among others. The method allows for the introduction of different substituents at C-1 and C-8 in the final isoquinolines regio- and stereoselectively, leading to the synthesis of a variety of enantiopure isoquinoline derivatives with four stereocenters, three of which are contiguous, and with known absolute configuration. The conclusions of the research highlight the efficiency of this concise and stereocontrolled synthetic method for potentially important biologically active molecules, demonstrating a five-step synthesis from the easily accessible (-)-8-aminomenthol.