Xn:Harmful;
90-12-0Relevant articles and documents
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Gilman,Moore
, p. 1843,1846 (1940)
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Buehler
, p. 1558 (1968)
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Radiation-induced C-C Bond Cleavage in 1,2-Diarylethanes as Model compounds of Coal. Part 1.- Pulse and Steady-state Radiolysis of 1,2-Di(1-naphthyl)ethane
Haenel, Matthias W.,Richter, Udo-Burckhard,Solar, Sonja,Getoff, Nikola
, p. 311 - 319 (1990)
1,2-Di(1-naphthyl)ethane (1,2-DNE) has been used to study the radiation-induced C-C bond cleavage of the ethane linkage.Pulse radiolysis was applied both in the absence and presence of NaAlH4 and NaAlH2(OR)2 used as scavengers for solvent cations.In the presence of the sodium aluminium hydrides the radical anions of 1,2-DNE are stabilized by the metal cation, resulting in the formation of radical anion/sodium cation pairs (Na+, 1,2-DNE.-), these species have a rather long lifetime (τ>2 ms) in DME as well as in THF, and show three absorption bands at 330, 370 and 750 nm.In THF ε370=14000 dm3 mol-1 cm-1 and ε750=5000 dm3 mol-1 cm-1 were established.Cleavage of the ethano bridge of 1,2-DNE was achieved by means of steady-state as well as multi-pulse radiolysis in the presence of alkali-metal aluminium hydrides.The efficiency of this process was studied by using NaAlH4, NaAlH2(OR)2, NaAlH2Et2, NaAlEt4 and LiAlH4 in THF as well as in DME.The most efficient C-C bond cleavage results from the successive attack of two sodium cation/electron ion pairs (Na+, e-) forming the unstable dianions (2 Na+, 1,2-DNE2-).These decompose under scission of the ethano bridge, producing naphthylmethyl carbanionic fragments C10H7CH2-Na+ which supposedly form aluminate salts, e.g.C10H7CH2AlH3-Na+, with AlH3 generated in the scavenging processes.From these aluminate salts 1-methylnaphthalene is obtained through hydrolysis.
Metal-Organic Framework-Confined Single-Site Base-Metal Catalyst for Chemoselective Hydrodeoxygenation of Carbonyls and Alcohols
Antil, Neha,Kumar, Ajay,Akhtar, Naved,Newar, Rajashree,Begum, Wahida,Manna, Kuntal
supporting information, p. 9029 - 9039 (2021/06/28)
Chemoselective deoxygenation of carbonyls and alcohols using hydrogen by heterogeneous base-metal catalysts is crucial for the sustainable production of fine chemicals and biofuels. We report an aluminum metal-organic framework (DUT-5) node support cobalt(II) hydride, which is a highly chemoselective and recyclable heterogeneous catalyst for deoxygenation of a range of aromatic and aliphatic ketones, aldehydes, and primary and secondary alcohols, including biomass-derived substrates under 1 bar H2. The single-site cobalt catalyst (DUT-5-CoH) was easily prepared by postsynthetic metalation of the secondary building units (SBUs) of DUT-5 with CoCl2 followed by the reaction of NaEt3BH. X-ray photoelectron spectroscopy and X-ray absorption near-edge spectroscopy (XANES) indicated the presence of CoII and AlIII centers in DUT-5-CoH and DUT-5-Co after catalysis. The coordination environment of the cobalt center of DUT-5-Co before and after catalysis was established by extended X-ray fine structure spectroscopy (EXAFS) and density functional theory. The kinetic and computational data suggest reversible carbonyl coordination to cobalt preceding the turnover-limiting step, which involves 1,2-insertion of the coordinated carbonyl into the cobalt-hydride bond. The unique coordination environment of the cobalt ion ligated by oxo-nodes within the porous framework and the rate independency on the pressure of H2 allow the deoxygenation reactions chemoselectively under ambient hydrogen pressure.
Cobalt?NHC Catalyzed C(sp2)?C(sp3) and C(sp2)?C(sp2) Kumada Cross-Coupling of Aryl Tosylates with Alkyl and Aryl Grignard Reagents
Piontek, Aleksandra,Och?dzan-Siod?ak, Wioletta,Bisz, Elwira,Szostak, Michal
, p. 202 - 206 (2020/12/01)
The first cobalt-catalyzed cross-coupling of aryl tosylates with alkyl and aryl Grignard reagents is reported. The catalytic system uses CoF3 and NHCs (NHC=N-heterocyclic carbene) as ancillary ligands. The reaction proceeds via highly selective C?O bond functionalization, leading to the corresponding products in up to 98 % yield. The employment of alkyl Grignard reagents allows to achieve a rare C(sp2)?C(sp3) cross-coupling of C?O electrophiles, circumventing isomerization and β-hydride elimination problems. The use of aryl Grignards leads to the formation of biaryls. The C?O cross-coupling sets the stage for a sequential cross-coupling by exploiting the orthogonal selectivity of the catalytic system.
Synthesis of renewable alkylated naphthalenes with benzaldehyde and angelica lactone
Cong, Yu,Li, Guangyi,Li, Ning,Wang, Aiqin,Wang, Ran,Wang, Xiaodong,Xu, Jilei,Zhang, Tao
supporting information, p. 5474 - 5480 (2021/08/16)
Herein, we report a new route for the synthesis of renewable alkylated naphthalenes (ANs) with benzaldehyde and angelica lactone, two platform compounds that can be derived from lignocellulose.
