127-00-4Relevant articles and documents
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Baerns,Sticken
, p. 1479 (1969)
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Takeichi et al.
, p. 2614 (1979)
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Influence of the metal (Al, Cr, and Co) and substituents of the porphyrin in controlling reactions involved in copolymerization of propylene oxide and carbon dioxide by porphyrin metal(III) complexes. 3. Cobalt chemistry
Chatterjee, Chandrani,Chisholm, Malcolm H.,El-Khaldy, Adnan,McIntosh, Ruaraidh D.,Miller, Jeffrey T.,Wu, Tianpin
, p. 4547 - 4553 (2013)
A series of cobalt(III) complexes LCoX, where L = 5,10,15,20- tetraphenylporphyrin (TPP), 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin (TFPP), and 2,3,7,8,12,13,17,18-octaethylporphyirn (OEP) and X = Cl or acetate, has been investigated for homopolymerization of propylene oxide (PO) and copolymerization of PO and CO2 to yield polypropylene oxide (PPO) and polypropylene carbonate (PPC) or propylene carbonate (PC), respectively. These reactions were carried out both with and without the presence of a cocatalyst, namely, 4-dimethylaminopyridine (DMAP) or PPN+Cl- (bis(triphenylphosphine)iminium chloride). The PO/CO2 copolymerization process is notably faster than PO homopolymerization. With ionic PPN+Cl- cocatalyst the TPPCoOAc catalyst system grows two chains per Co center and the presence of excess [Cl-] facilitates formation of PC by two different backbiting mechanisms during copolymerization. Formation of PPC is dependent on both [Cl-] and the CO2 pressure employed (1-50 bar). TPPCoCl and PO react to form TPPCo(II) and ClCH2CH(Me)OH, while with DMAP, TPPCoCl yields TPPCo(DMAP)2+Cl-. The reactions and their polymers and other products have been monitored by various methods including react-IR, FT-IR, GPC, ESI, MALDI TOF, EXAFS, and NMR (1H, 13C{1H}) spectroscopy. Notable differences are seen in these reactions with previous studies of (porphyrin)M(III) complexes (M = Al, Cr) and of the (salen)M(III) complexes where M = Cr, Co.
Primary Alcohols via Nickel Pentacarboxycyclopentadienyl Diamide Catalyzed Hydrosilylation of Terminal Epoxides
Lambert, Tristan H.,Steiniger, Keri A.
supporting information, p. 8013 - 8017 (2021/10/25)
The efficient and regioselective hydrosilylation of epoxides co-catalyzed by a pentacarboxycyclopentadienyl (PCCP) diamide nickel complex and Lewis acid is reported. This method allows for the reductive opening of terminal, monosubstituted epoxides to form unbranched, primary alcohols. A range of substrates including both terminal and nonterminal epoxides are shown to work, and a mechanistic rationale is provided. This work represents the first use of a PCCP derivative as a ligand for transition-metal catalysis.
One-Pot Biocatalytic Double Oxidation of α-Isophorone for the Synthesis of Ketoisophorone
Tavanti, Michele,Parmeggiani, Fabio,Castellanos, J. Rubén Gómez,Mattevi, Andrea,Turner, Nicholas J.
, p. 3338 - 3348 (2017/09/13)
The chemical synthesis of ketoisophorone, a valuable building block of vitamins and pharmaceuticals, suffers from several drawbacks in terms of reaction conditions and selectivity. Herein, the first biocatalytic one-pot double oxidation of the readily available α-isophorone to ketoisophorone is described. Variants of the self-sufficient P450cam-RhFRed with improved activity have been identified to perform the first step of the designed cascade (regio- and enantioselective allylic oxidation of α-isophorone to 4-hydroxy-α-isophorone). For the second step, the screening of a broad panel of alcohol dehydrogenases (ADHs) led to the identification of Cm-ADH10 from Candida magnoliae. The crystal structure of Cm-ADH10 was solved and docking experiments confirmed the preferred position and geometry of the substrate for catalysis. The synthesis of ketoisophorone was demonstrated both as a one-pot two-step process and as a cascade process employing designer cells co-expressing the two biocatalysts, with a productivity of up to 1.4 g L?1 d?1.
PROCESS FOR HYDROGENATING DICHLOROISOPROPYL ETHER
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Page/Page column 5, (2016/04/20)
Convert dichloroisopropyl ether into a halogenated derivative by contacting the dichloroisopropyl ether with a source of hydrogen and a select heterogeneous hydrogenation catalyst under process conditions selected from a combination of a temperature within a range of from 50 degrees centigrade (oC) to 350 oC, a pressure within a range of from atmospheric pressure (0.1 megapascals) to 1000 pounds per square inch (6.9 MPa), a liquid feed volume flow to catalyst mass ratio between 0.5 and 10 L/Kg*h and a volume hydrogen / volume liquid ratio between 100 and 5000 ml gas/ ml liquid. The halogenated derivative is at least one of 1-chloro-2-propanol and 1,2-dichloropropane 1, and glycerin monochlorohydrin.
