206-44-0Relevant academic research and scientific papers
Bicyclohexene- peri-naphthalenes: Scalable Synthesis, Diverse Functionalization, Efficient Polymerization, and Facile Mechanoactivation of Their Polymers
Yang, Jinghui,Horst, Matias,Werby, Sabrina H.,Cegelski, Lynette,Burns, Noah Z.,Xia, Yan
, p. 14619 - 14626 (2020)
Pursuing polymers that can transform from a nonconjugated to a conjugated state under mechanical stress to significantly change their properties, we developed a new generation of ladder-type mechanophore monomers, bicyclo[2.2.0]hex-5-ene-peri-naphthalene (BCH-Naph), that can be directly and efficiently polymerized by ring-opening metathesis polymerization (ROMP). BCH-Naphs can be synthesized in multigram quantities and functionalized with a wide range of electron-rich and electron-poor substituents, allowing tuning of the optoelectronic and physical properties of mechanically generated conjugated polymers. Efficient ROMP of BCH-Naphs yielded ultrahigh molecular weight polymechanophores with controlled MWs and low dispersity. The resulting poly(BCH-Naph)s can be mechanically activated into conjugated polymers using ultrasonication, grinding, and even simple stirring of the dilute solutions, leading to changes in absorption and fluorescence. Poly(BCH-Naph)s represent an attractive polymechanophore system to explore multifaceted mechanical response in solution and solid states, owing to the synthetic scalability, functional diversity, efficient polymerization, and facile mechanoactivation.
A Microsynthesis of Fluoranthene
Maly, Ernest
, p. 1103 - 1104 (1981)
A simple synthesis of fluoranthene based on the distillation of benzanthrone with zinc dust is described, in addition to those cited in Clar's monograph.It may be useful for small scale preparations of this polycyclic hydrocarbon.The pure product was obtained by chromatography. - Keywords: Polycyclic hydrocarbon; Zinc dust distillation
Novel and rapid palladium-assisted 6π electrocyclic reaction affording 9,10-dihydrophenanthrene and its analogues
Jana, Rathin,Chatterjee, Indranil,Samanta, Shubhankar,Ray, Jayanta K.
, p. 4795 - 4797 (2008)
(Equation Presented) A novel methodology for the synthesis of 9,10-dihydrophenanthrene and its analogues has been developed via a palladium-assisted 6π electrocyclic reaction followed by formaldehyde elimination.
Steric Hindrance Facilitated Synthesis of Enynes and Their Intramolecular [4 + 2] Cycloaddition with Alkynes
Gonzalez, Juan J.,Francesch, Andres,Cardenas, Diego J.,Echavarren, Antonio M.
, p. 2854 - 2857 (1998)
The palladium-catalyzed insertion of 1-alkynes into internal alkynes which are bent out of linearity by the interference with a peri or ortho substituent led to enynes regioselectively. The resulting enynes undergo a new type of intramolecular thermal cycloaddition, which can be used for the annulation of an aryl ring onto naphthalene derivatives to afford fluranthenes. The cyclization of (E)-1-(1-buten-3-ynyl)-8-ethynylnaphthalene could also be performed in the presence of a Cu(I) catalyst at room temperature.
Phenyl migrations in dehydroaromatic compounds. A new mechanistic link between alternant and nonalternant hydrocarbons at high temperatures
Preda, Dorin V.,Scott, Lawrence T.
, p. 1489 - 1492 (2000)
(Matrix presented) Flash vacuum pyrolysis of benzo[b]biphenylene, an alternant polycyclic aromatic hydrocarbon (PAH), gives fluoranthene, a nonalternant PAH, as the major product at 1100 °C in the gas phase. The most reasonable mechanism to explain this isomerization involves equilibrating diradicals of 2-phenylnaphthalene that rearrange by the net migration of a phenyl group to give equilibrating diradicals of 1-phenylnaphthalene, one isomer of which then cyclizes to fluoranthene.
Tellurium-Mediated Cycloaromatization of Acyclic Enediynes under Mild Conditions
Landis, Chad A.,Payne, Marcia M.,Eaton, David L.,Anthony, John E.
, p. 1338 - 1339 (2004)
The cycloaromatization of acyclic enediynes typically requires very high temperatures (>160 °C) and dilute conditions to proceed in a synthetically useful yield. These conditions hinder reaction throughput, inhibiting the use of this reaction for the large-scale production of materials. The reaction of sodium telluride with acyclic arenediynes yields the corresponding tellurepine, which under gentle heating extrudes Te° to yield the cycloaromatization product. We have developed conditions that form sodium telluride from inexpensive tellurium metal in situ, and that also perform the desilylation of silylated arenediynes in the same process. Under our conditions, we are able to perform desilylation and cycloaromatization at temperatures as low as 40 °C and on a scale as large as 5 g in standard laboratory glassware. Copyright
Synthesis of Polycyclic Aromatic Hydrocarbons by Phenyl Addition–Dehydrocyclization: The Third Way
Zhao, Long,Prendergast, Matthew B.,Kaiser, Ralf I.,Xu, Bo,Ablikim, Utuq,Ahmed, Musahid,Sun, Bing-Jian,Chen, Yue-Lin,Chang, Agnes H. H.,Mohamed, Rana K.,Fischer, Felix R.
supporting information, p. 17442 - 17450 (2019/11/11)
Polycyclic aromatic hydrocarbons (PAHs) represent the link between resonance-stabilized free radicals and carbonaceous nanoparticles generated in incomplete combustion processes and in circumstellar envelopes of carbon rich asymptotic giant branch (AGB) stars. Although these PAHs resemble building blocks of complex carbonaceous nanostructures, their fundamental formation mechanisms have remained elusive. By exploring these reaction mechanisms of the phenyl radical with biphenyl/naphthalene theoretically and experimentally, we provide compelling evidence on a novel phenyl-addition/dehydrocyclization (PAC) pathway leading to prototype PAHs: triphenylene and fluoranthene. PAC operates efficiently at high temperatures leading through rapid molecular mass growth processes to complex aromatic structures, which are difficult to synthesize by traditional pathways such as hydrogen-abstraction/acetylene-addition. The elucidation of the fundamental reactions leading to PAHs is necessary to facilitate an understanding of the origin and evolution of the molecular universe and of carbon in our galaxy.
Mechanisms of Heptane Degradation and Product Formation in Microwave Discharge
Bobkova,Stokolos,Garifullin
, p. 336 - 340 (2019/08/15)
Abstract: A mechanism for the degradation of n-heptane and the formation of the products of its plasma-chemical transformation by microwave discharge treatment has been proposed. Chemical reactions resulting in reactive species, namely free radicals that form lower hydrocarbons and polyaromatic structures are presented. The product composition of the gas, liquid, and solid phases has been studied using gas chromatography–mass spectrometry analysis of the precipitate obtained by evaporation of the liquid phase after the treatment of n-heptane.
Pd-Catalyzed Annulation of 1-Halo-8-arylnaphthalenes and Alkynes Leading to Heptagon-Embedded Aromatic Systems
Yan, Jianming,Rahman, Md. Shafiqur,Yoshikai, Naohiko
, p. 9395 - 9399 (2019/01/04)
A palladium-catalyzed heptagon-forming annulation reaction between 1-halo-8-arylnaphthalene and diarylacetylene is reported. The reaction is promoted using a catalytic system comprised of Pd(OAc)2, moderately electron-deficient triarylphosphine P(4-ClC6H4)3, and Ag2CO3 to afford benzo[4,5]cyclohepta[1,2,3-de]naphthalene derivatives in moderate to good yields, in preference to fluoranthene as a competing byproduct. Twofold annulation can also be achieved to access a novel heptagon-embedded polycyclic aromatic hydrocarbon compound.
Intramolecular Remote C-H Activation via Sequential 1,4-Palladium Migration to Access Fused Polycycles
Li, Panpan,Li, Qiuyu,Weng, He,Diao, Jiaming,Yao, Hequan,Lin, Aijun
supporting information, p. 6765 - 6769 (2019/09/07)
An unprecedented intramolecular remote C-H activation via sequential 1,4-palladium migration with an aromatic ring as a conveyor has been described. This reaction provides an efficient route to construct diverse polycyclic frameworks in moderate to good yield via palladium-catalyzed remote C-H activation/alkene insertion, arylation, alkenylation, and the Heck reaction. The preliminary mechanistic studies revealed that the 1,4-palladium migration process was reversible.
