959-02-4Relevant articles and documents
Birch Reduction of Aromatic Compounds by Inorganic Electride [Ca2N]+?e- in an Alcoholic Solvent: An Analogue of Solvated Electrons
Yoo, Byung Il,Kim, Ye Ji,You, Youngmin,Yang, Jung Woon,Kim, Sung Wng
supporting information, p. 13847 - 13853 (2018/11/23)
Birch reduction of aromatic systems by solvated electrons in alkali metal-ammonia solutions is widely recognized as a key reaction that functionalizes highly stable π-conjugated organic systems. In spite of recent advances in Birch reduction with regard to reducing agent and reaction conditions, there remains an ongoing challenge to develop a simple and efficient Birch reaction under mild conditions. Here, we demonstrate that the inorganic electride [Ca2N]+?e- promotes the Birch reduction of polycyclic aromatic hydrocarbons (PAHs) and naphthalene under alcoholic solvent in the vicinity of room temperature as a solid-type analogy to solvated electrons in alkali metal ammonia solutions. The anionic electrons from electride [Ca2N]+?e- are transferred to PAHs and naphthalene via alcoholysis in a polar cosolvent medium. It is noteworthy that a high conversion yield to the hydrogenated products is ascribed to the extremely high electron transfer efficiency of 98%. This simple protocol utilizing an inorganic electride offers a direct and practical strategy for the reduction of aromatic compounds and provides an outstanding reducing agent for synthetic chemistry.
METHOD FOR THE PREPARATION OF A PARTIALLY HYDROGENATED POLYACENE AND AN INTERMEDIATE THEREOF
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, (2018/02/28)
The present invention relates to a process for preparing a partially hydrogenated polyacene, and a novel intermediate used in such process; also the present invention relates to a process for preparing the corresponding conjugated polyacenes.
Hydroacenes Made Easy by Gold(I) Catalysis
Dorel, Ruth,McGonigal, Paul R.,Echavarren, Antonio M.
supporting information, p. 11120 - 11123 (2016/10/13)
A novel strategy for the synthesis of partially saturated acene derivatives has been developed based on a AuI-catalyzed cyclization of 1,7-enynes. This method provides straightforward access to stable polycyclic products featuring the backbone of the acene series, up to nonacene.
Determination of the effective redox potentials of SmI2, SmBr2, SmCl2, and their complexes with water by reduction of aromatic hydrocarbons. Reduction of anthracene and stilbene by samarium(II) iodide-water complex
Szostak, Michal,Spain, Malcolm,Procter, David J.
, p. 2522 - 2537 (2014/04/17)
Samarium(II) iodide-water complexes are ideally suited to mediate challenging electron transfer reactions, yet the effective redox potential of these powerful reductants has not been determined. Herein, we report an examination of the reactivity of SmI2(H2O)n with a series of unsaturated hydrocarbons and alkyl halides with reduction potentials ranging from -1.6 to -3.4 V vs SCE. We found that SmI 2(H2O)n reacts with substrates that have reduction potentials more positive than -2.21 V vs SCE, which is much higher than the thermodynamic redox potential of SmI2(H2O) n determined by electrochemical methods (up to -1.3 V vs SCE). Determination of the effective redox potential demonstrates that coordination of water to SmI2 increases the effective reducing power of Sm(II) by more than 0.4 V. We demonstrate that complexes of SmI2(H 2O)n arising from the addition of large amounts of H 2O (500 equiv) are much less reactive toward reduction of aromatic hydrocarbons than complexes of SmI2(H2O)n prepared using 50 equiv of H2O. We also report that SmI 2(H2O)n cleanly mediates Birch reductions of substrates bearing at least two aromatic rings in excellent yields, at room temperature, under very mild reaction conditions, and with selectivity that is not attainable by other single electron transfer reductants.
Metal-free hydrogenation catalysis of polycyclic aromatic hydrocarbons
Segawa, Yasutomo,Stephan, Douglas W.
supporting information, p. 11963 - 11965 (2013/01/16)
The frustrated Lewis pair, B(C6F5) 3/Ph2PC6F5, acts as an efficient catalyst for the hydrogenation of the polycyclic hydrocarbons including anthracene derivatives, tetracene and tetraphene, at 80 °C and 100 atm H2 pressure via a mechanism involving protonation of polyaromatic species followed by hydride transfer. The Royal Society of Chemistry.
Synthesis of acenes via coupling of 1,4-dilithiobutadienes with diiodoarenes in the presence of CuCl
Zhou, Lishan,Nakajima, Kiyohiko,Kanno, Ken-ichiro,Takahashi, Tamotsu
supporting information; experimental part, p. 2722 - 2726 (2009/09/06)
Dilithiobutadienes prepared from diiodobutadienes reacted with diiodobenzene or diiodonaphthalene to afford substituted naphthalene, anthracene, dihydronaphthacene, and dihydropentacene derivatives in the presence of CuCl and DMPU. Dihydronaphthacene and
Unexpected photooxidation of H-bonded tetracene
Liang, Zhixiong,Zhao, Wei,Wang, Shenglong,Tang, Qin,Lam, Sheung-Chuen,Miao, Qian
supporting information; experimental part, p. 2007 - 2010 (2009/04/18)
In our attempts of tuning the molecular packing of tetracene with H-bonding, we found that tetracenediamide was much more vulnerable to photooxidation than tetracene in crystals despite their similar sensitivity to photooxidation In solution. Unexpectedly photooxidation of tetracenediamide in solution and in crystals show different regioselectivities. To explain the regioselectivity, a mechanism Involving H-bonding is proposed. This study Indicates that molecular packing in solid state can play an important role In solid-gas reactions.
Hydrogenation of arenes by dual activation: Reduction of substrates ranging from benzene to C60 fullerene under ambient conditions
Deshmukh, Ravindra R.,Lee, Ji Woong,Shin, Ueon Sang,Lee, Jin Yong,Song, Choong Eui
supporting information; body text, p. 8615 - 8617 (2009/05/15)
(Chemical Equation Presented) Tackling aromaticity: The title reaction was accomplished by simultaneous activation of molecular hydrogen and the aromatic substrate by Pd/C and a Lewis acidic ionic liquid, respectively. Even benzene and C60 fullerene were hydrogenated under ambient conditions (1 bar of H2 at room temperature). An ionic hydrogenation mechanism (see scheme) is supported by characterization of a stabilized arenium intermediate.
Hydrogen-protected acenes
Athans, Andreas J.,Briggs, Jonathan B.,Jia, Wenling,Miller, Glen P.
, p. 2636 - 2641 (2008/09/20)
The first systematic study concerning the hydrogenation of acenes and acene quinones is presented. Phenyl substituted acenes and acene quinones are hydrogenated in excellent yield and with complete regioselectivity using HI-AcOH. The resulting H-protected acenes bear alternating aromatic and non-aromatic rings and are stable, soluble molecules that may be stored indefinitely and then deprotected to afford the parent acenes. In this manner, H-protected acenes have been utilized in the syntheses of several [60]fullerene-acene adducts. Buckminsterfullerene also hydrogenates in HI-AcOH yielding C3v symmetric C60H18. The Royal Society of Chemistry.
Characterization of polycyclic aromatic hydrocarbon particulate and gaseous emissions from polystyrene combustion
Durlak, Susan K.,Biswas, Pratim,Shi, Jichun,Bernhard, Mary Jo
, p. 2301 - 2307 (2007/10/03)
The partitioning of polycyclic aromatic hydrocarbons (PAHs) between the particulate and gaseous phases resulting from the combustion of polystyrene was studied. A vertical tubular flow furnace was used to incinerate polystyrene spheres (100-300 μm) at different combustion temperatures (800- 1200 °C) to determine the effect of temperature and polystyrene feed size on the particulate and gaseous emissions and their chemical composition. The furnace reactor exhaust was sampled using real-time instruments (differential mobility particle sizer and/or optical particle counter) to determine the particle size distribution. For chemical composition analyses, the particles were either collected on Teflon filters or split into eight size fractions using a cascade impactor with filter media substrates, while the gaseous products were collected on XAD-2 adsorbent. Gas chromatography/mass spectroscopy (GC/MS) was used to identify and quantify the specific PAH species, their partitioning between the gas and particulate phases, and their distribution as a function of emission particle size. The total mass and number of PAH species in both the particulate and gas phases were found to decrease with increasing incineration temperature and decreasing polystyrene feed size, while the mean diameter of the particles increases with increasing incineration temperature and decreasing feed size. In addition, the PAH species in the particulate phase were found to be concentrated in the smaller aerosol sizes. The experimental results have been analyzed to elucidate the formation mechanisms of PAHs and particles during polystyrene combustion. The implications of these results are also discussed with respect to the control of PAH emissions from municipal waste-to-energy incineration systems. The partitioning of polycyclic aromatic hydrocarbons (PAHs) between particulate and gaseous phases resulting from the combustion of polystyrene was studied. A vertical tubular flow furnace was used to incinerate polystyrene spheres to determine the effect of temperature and polystyrene feed size on the particulate and gaseous emissions and their chemical composition. The furnace reactor exhaust was sampled using real-time instruments to determine the particle size distribution. The total mass and number of PAH species in both the particulate and gas phases were found to decrease with increasing incineration temperature and decreasing polystyrene feed size, while the mean diameter of the particles increases with increasing incineration temperature and decreasing feed size. In addition, the PAH species in the particulate phase were found to be concentrated in the smaller aerosol sizes.
