571-58-4Relevant articles and documents
Riemschneider,Foerster
, p. 616 (1962)
"off-on" switching of intracellular singlet oxygen release under biocompatible conditions
Ucar, Esma,Xi, Dongmei,Seven, Ozlem,Kaya, Cansu,Peng, Xiaojun,Sun, Wen,Akkaya, Engin U.
, p. 13808 - 13811 (2019)
Precise spatiotemporal control of singlet oxygen generation is of immense importance considering its involvement in photodynamic therapy. In this work, we present a rational design for an endoperoxide which is highly stable at ambient temperatures yet, can rapidly be converted into a highly labile endoperoxide, thus releasing the "stored" singlet oxygen on demand. The "off-on" chemical switching from the stable to the labile form is accomplished by the reaction with fluoride ions. The potential utility of controlled singlet oxygen release was demonstrated in cell cultures.
Tetrahydronaphthalene-1,4-dione and its chromiumtricarbonyl complex
Garcia, Alvaro Enriquez,Kuendig, E. Peter,Lomberget, Thierry,Bragg, Ryan,Poulard, Cyril,Bernardinelli, Gerald
, p. 169 - 171 (2007)
The article gives a brief outline of the rediscovery of tetrahydronaphthalene-1,4-dione, a stable tautomer which has been known for over half a century but has not been applied in synthesis. Desymmetrization is readily achieved via enantioselective reduction. Synthetic potential apart, the dione and its chromiumthcarbonyl complex are of theoretical interest. Thus, whereas dihydroxynaphthalene requires quite harsh conditions and leads to a 1:1 mixture of the two tautomers, the chromiumtricarbonyl complex of dihydroxynaphthalene tautomerizes under very mild conditions to the tetrahydronaphthalene-1,4-dione complex. An earlier literature report showed that in trifluoroacetic acid, the dione tautomer is present exclusively. This has now been used to isolate multigram quantities of the compound. Schweizerische Chemische Gesellschaft.
Formal total synthesis of (±)-occidol
Vera, William J.,Banerjee, Ajoy K.
, p. 3091 - 3094 (2006)
The conversion of tetralone 1 to methylketone 7, a valuable intermediate of occidol 8, has been accomplished in four steps (reduction, mesylation, cyanation, and Grignard reaction with methylmagnesium bromide). Copyright Taylor & Francis Group, LLC.
Nonradiative deactivation of singlet oxygen (1O2) by cubane and its derivatives
Lancaster, Jeffrey R.,Marti, Angel A.,Lopez-Gejo, Juan,Jockusch, Steffen,O'Connor, Naphtali,Turro, Nicholas J.
, p. 5509 - 5512 (2008)
(Chemical Equation Presented) The bimolecular quenching rate constants of singlet oxygen (1O2) by cubane and cubane derivatives were determined and found to be in the order of 103-104 M -1 s-1. These values represent larger values than expected for aliphatic alkanes as a model for C-H vibrational deactivation. This result is explained by the occurrence of two different deactivation mechanisms: energy transfer to cubane C-H vibrational modes and the formation of a charge-transfer complex between 1O2 and cubane (1O 2?- ...cubane?+).
The Reactions of O2 (1Δg) with Anancomeric 1,3-Dithianes. The First Experimental Evidence in Support of a Hydroperoxy Sulfonium Ylide as a Precursor to Sulfoxide on the Sulfide Singlet Oxygen Reaction Surface
Toutchkine,Clennan
, p. 5620 - 5625 (1999)
The kinetic isotope effects for the formation of anancomeric 1,3-dithiane-1-oxides in the reactions of singlet oxygen with the parent 1,3-dithianes have been determined for a series of 2-protio and 2-deuterio analogues. The substantial isotope effects are used to argue for formation of a hydroperoxysulfonium ylide as a key intermediate in sulfoxide formation. These results confirm an earlier theoretical prediction and force a change in the currently accepted mechanism for this important reaction. The first experimental demonstration of a novel singlet oxygen-induced epimerization of a 1,3-dithiane and a novel intramolecular electron transfer within a hydroperoxysulfonium ylide are also reported.
Methylation of 2-methylnaphthalene over metal-impregnated mesoporous MCM-41 for the synthesis of 2,6-triad dimethylnaphthalene isomers
Niftaliyeva, Aysel,Güle?, Fatih,Karaduman, Ali
, p. 2403 - 2416 (2020)
2,6-Dimethylnaphthalene (2,6-DMN) is one of the key intermediates for the production of polyethylene naphthalate (PEN), which demonstrates superior properties compared with the polyethylene terephthalate. However, the complex synthesis procedure of 2,6-DMN increases the production cost and decreases the commercialisation of PEN. In this study, selective synthesis of 2,6-triad DMN isomers (1,5-DMN, 1,6-DMN and 2,6-DMN) has been investigated by the methylation of 2-methylnaphthalene (2-MN) over mesoporous Cu/MCM-41 and Zr/MCM-41 zeolite catalysts. On the contrary of other DMN isomers, 2.6-triad isomers can effectively be converted to be profitable 2,6-DMN with an additional isomerisation reaction, which is a new approach to reach higher 2,6-DMN yield. The methylation reactions of 2-MN were investigated in a fixed-bed reactor at 400?°C and weight hourly space velocity of 1–3?h?1. The results showed that the activity of MCM-41 on the methylation of 2-MN has been enhanced with the impregnation of Cu. The conversion increased from about 17% to 35 wt% with the impregnation of Cu. Similarly, the 2,6-triad DMN selectivity and 2,6-/2,7-DMN ratio reached the maximum level (48 wt% and 1.95, respectively) over Cu-impregnated MCM-41 zeolite catalyst.
Synthesis method of 1,4-dimethylnaphthalene
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Paragraph 0032-0048, (2021/06/23)
The invention discloses a synthesis method of 1,4-dimethylnaphthalene, and belongs to the technical field of organic synthesis. In order to reduce the production cost of 1,4-dimethylnaphthalene and realize industrial production, the invention provides a synthesis method of 1,4-dimethylnaphthalene, which comprises the following steps: reacting 4-bromomethylnaphthalene as a raw material with a methyl magnesium halide Grignard reagent in the presence of a nickel catalyst to obtain 1,4-dimethylnaphthalene, wherein the nickel catalyst is a nickel complex of nickel chloride and a ligand, and the ligand is selected from triethyl phosphite, bis(triphenylphosphine), bis(tricyclohexylphosphine), 4,4'-dimethyl-2,2'-bipyridine or 2-phenyl-4,5-dihydro-1H-imidazole. By optimizing the reaction conditions, selecting the specific nickel catalyst and controlling the reaction temperature, the high-purity 1, 4-dimethylnaphthalene can be obtained at high yield under the mild reaction conditions, the raw materials are cheap and easy to obtain, the production cost is remarkably reduced, and industrial production is facilitated.
Iron-Catalyzed Direct Julia-Type Olefination of Alcohols
Landge, Vinod G.,Babu, Reshma,Yadav, Vinita,Subaramanian, Murugan,Gupta, Virendrakumar,Balaraman, Ekambaram
, p. 9876 - 9886 (2020/09/03)
Herein, we report an iron-catalyzed, convenient, and expedient strategy for the synthesis of styrene and naphthalene derivatives with the liberation of dihydrogen. The use of a catalyst derived from an earth-abundant metal provides a sustainable strategy to olefins. This method exhibits wide substrate scope (primary and secondary alcohols) functional group tolerance (amino, nitro, halo, alkoxy, thiomethoxy, and S- A nd N-heterocyclic compounds) that can be scaled up. The unprecedented synthesis of 1-methyl naphthalenes proceeds via tandem methenylation/double dehydrogenation. Mechanistic study shows that the cleavage of the C-H bond of alcohol is the rate-determining step.
