76670-39-8Relevant academic research and scientific papers
Convenient Phenacene Synthesis by Sequentially Performed Wittig Reaction and Mallory Photocyclization Using Continuous-Flow Techniques
Okamoto, Hideki,Takahashi, Haruhiko,Takane, Takamitsu,Nishiyama, Yasuhiro,Kakiuchi, Kiyomi,Gohda, Shin,Yamaji, Minoru
, p. 2949 - 2957 (2017/06/27)
Various phenacenes possessing chrysene, picene, and fulminene frameworks were prepared by using a continuous-flow synthetic protocol in which Wittig reaction affording diarylethenes and their Mallory photocyclization producing phenacene skeletons were sequentially performed. The Wittig reaction solution, containing the diaryl ethene obtained from an arylaldehyde and an arylmethyltriphenylphosphonium salt, was mixed with an iodine solution in the flow system and, subsequently, the solution was subjected to the photoreaction. Desired phenacenes were obtained with high to moderate chemical yield. For the present protocol, isolation of the intermediary diarylethene, which is the key precursor of the phenacene, is unnecessary. The approach provides a convenient method to supply a variety of phenacene samples, which are needed for initial systematic surveys in material science.
Tetracarboxy-Functionalized [8]-, [10]-, [12]-, and [14]Phenacenes
Moreira, Thamires S.,Ferreira, Marli,Dall'armellina, Alice,Cristiano, Rodrigo,Gallardo, Hugo,Hillard, Elizabeth A.,Bock, Harald,Durola, Fabien
supporting information, p. 4548 - 4551 (2017/08/30)
Mono- and diglyoxylation of chrysene and naphthalene leads to Perkin reactants that yield bismaleates, which efficiently photocyclize to elongated phenacenetetracarboxylic esters. Their band gaps remain significantly larger than the value postulated for p
An investigation of the scope of the 1,7-electrocyclization of α,β:γ,δ-conjugated azomethine ylides
Zhang, Weimin,Ning, Fuqiang,Váradi, Linda,Hibbs, David E.,Platts, James A.,Nyerges, Miklós,Anderson, Rosaleen J.,Groundwater, Paul W.
supporting information, p. 3621 - 3629 (2014/05/20)
Substituents on the diene component have little influence on the periselectivity of the cyclizations of α,β:γ,δ-conjugated azomethine ylides, with 1,7-electrocyclizations predominating. In some cases, subtle changes to these substituents can, however, influence the product formed, through their effect on the relative energies of the transition states for the 1,5- (6π) and 1,7-electrocyclization (8π) processes. The most striking changes in periselectivity occur for phenylethenyl-substituted azomethine ylides 3d-f, which can give either a pyrroline 4d,f or dihydrobenzazepine 6e, depending upon the alkene configuration.
Electrophilic aromatic reactivity. Part 27. Protiodetritiation of chrysene
Archer, William J.,Taylor, Roger,Gore, Peter H.,Kamounah, Fadhil S.
, p. 1828 - 1831 (2007/10/02)
All six monotritium-labelled chrysenes have been prepared, and their rates of protiodetritiation measured at 70°, using a mixture of trifluoroacetic acid-chloroform (9 : 1 v/v) as the exchanging medium. These lead to the following partial rate factors (positions in parentheses): 975 (1); 186 (2); 307 (3); 696 (4): 2790 (5); 12 200 (6) and the corresponding σ+ values are -0.342; -0.259; -0.284; -0.325; -0.394; -0.467. Hueckel localization energies predict a positional reactivity order, viz. 6 > 1 > 4 > 5 > 3 > 2 and reactivities relative to phenanthrene) close to that observed, only the 5-position being anomalous. Thus as in the case of helicenes, these calculations tend to underestimate the reactivity of the most central position in the molecule, though for chrysene, no localization of electrons at that point through ring distortion can be held responsible. Annelation rules, derived from hydrogen exchange data for other polycyclics, predict that the partial rate factor for the 5-position should be close to that observed. Reactivities in the terminal ring are only half that of the structural isomer benzo[c]phenanthrene (tetrahelicene) which further supports the view that distortion in the latter raises the reactivity through destabilization of the ground state. The relative reactivities of the unhindered positions in naphthalene, phenanthrene, and chrysene in acetylation are the inverse of that predicted by hydrogen exchange, and a possible reason for this is considered.
