97691-23-1Relevant articles and documents
Organic bifunctional catalyst and preparation method thereof as well as stereoregular biodegradable polyester and preparation method thereof
-
Paragraph 0119-0122, (2021/07/10)
The invention relates to an organic bifunctional catalyst and a preparation method thereof, and stereoregular biodegradable polyester and a preparation method thereof. The organic bifunctional catalyst disclosed by the invention is obtained by reacting isocyanate or isothiocyanate with a pyridylamine compound. According to the catalyst, an O-carboxyl intracyclic anhydride monomer and a pyridine nucleophilic addition monomer of an amino acid source are activated by thiourea, and controllable ring opening polymerization can be performed on an OCA monomer under a mild condition by utilizing an amplification effect of adjacent groups, so that functional polyester with high isotacticity and controllable molecular weight is prepared. The solvent used for polymerization can be chloroform, toluene, dichloromethane and the like, the polymerization temperature range is 25-50 DEG C, and the stereoregularity is adjustable between 60% and 90%. Under the polymerization condition, the monomer conversion rate can reach 99% within 24-48 hours. The molecular weight of the obtained polyester is controllable, and the melting point reaches up to 150 DEG C. The molecular weight of the polyester is changed between 20,000 and 100,000, and the polyester has a wide prospect for industrial application.
Construction of Bisbenzofuro[2,3-b:3′,2′-e]pyridines by Palladium-Catalyzed Double Intramolecular Oxidative C-H/C-H Coupling
Kaida, Hiroyuki,Goya, Tsuyoshi,Nishii, Yuji,Hirano, Koji,Satoh, Tetsuya,Miura, Masahiro
supporting information, p. 1236 - 1239 (2017/03/14)
The palladium-catalyzed intramolecular oxidative C-H/C-H coupling of 2-aryloxypyridines as challenging substrates is investigated to construct an important class of N,O-mixed heteroacenes, i.e. benzofuropyridines. It is found that 2,6-diaryloxypyridines e
The AZARYPHOS family of ligands for ambifunctional catalysis: Syntheses and use in ruthenium-catalyzed anti-markovnikov hydration of terminal alkynes
Hintermann, Lukas,Dang, Tuan Thanh,Labonne, Aurelie.,Kribber, Thomas,Xiao, Li,Naumov, Pance
supporting information; experimental part, p. 7167 - 7179 (2010/02/28)
The family of AZARYPHOS (aza-aryl-phosphane) phosphane ligands, containing a phosphine unit and sterically shielded nitrogen lone pairs in the ligand periphery, is introduced as a tool for developing ambifunctional catalysis by the metal center and nitrogen lone pairs in the ligand sphere. General synthetic strategies have been developed to synthesize over 25 examples of structurally diverse (6-aryl-2pyridyl)phosphanes (ARPYPHOS), (6alkyl-2-pyridyl)phosphanes (ALPY-PHOS), 4,6-disubsituted l,3-diazin-2ylphosphanes or l,3,5-triazin-2- ylphosphanes, quinazolinylphosphanes, quinolinylphosphanes, and others. The scalable syntheses proceed in a few steps. The incorporation of AZARYPHOS ligands (L) into complexes [RuCp(L)2(MeCN)][PF6] (Cp = cyclopentadieny1)gives catalysts for the anti-Markovnikov hydration of terminal alkynes of the highest known activities. Electronic and steric ligand effects modulate the reaction kinetics over a range of two orders of magnitude. These results highlight the importance of using structurally diverse ligand families in the process of developing cooperative ambifunctional catalysis by a metal and its ligand.