Use of External Radical Sources in Flash Vacuum Pyrolysis to Facilitate Cyclodehydrogenation Reactions in Polycyclic Aromatic Hydrocarbons

Amick, Aaron W.; Martin, Sara

doi:10.1071/ch14289

Cited by 4 publications

(3 citation statements)

References 45 publications

(54 reference statements)

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“…Recently, similar thermally induced aryl-aryl coupling reactions have also been reported for gas-phase polycyclic aromatic hydrocarbons. 50,51 Compared to these reports, the required temperature for the reaction in the present case is comparably low (only B400 K), which is attributed to the catalytic role of the Cu substrate. 52,53 It is important to note that the annealing temperature of about 400 K, which is necessary to initiate the dehydrogenation reaction on Cu(111), is much lower than the temperature of the Knudsen cell used to thermally evaporate the molecules onto the surface (about 690 K), which again underlines the catalytic activity of the substrate.…”

Section: Resultscontrasting

confidence: 72%

Self-assembly and coverage dependent thermally induced conformational changes of Ni(ii)-meso-tetrakis (4-tert-butylphenyl) benzoporphyrin on Cu(111)

Zhang

Lepper

Stark

et al. 2015

Phys. Chem. Chem. Phys.

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A systematic scanning tunnelling microscopy investigation of the self-assembly and of thermally induced conformational changes of Ni(II)-meso-tetrakis (4-tert-butylphenyl) benzoporphyrin (Ni-TTBPBP) onCu (111) is presented. At room temperature, Ni-TTBPBPs diffuse on the surface and self-assemble into ordered islands with well-defined registry to the substrate, with two different azimuthal orientations. The formation of the characteristic supramolecular structure is attributed to van der Waals interactions between the tert-butyl groups. Upon moderate heating, the intramolecular conformation changes irreversibly due to a dehydrogenative intramolecular aryl-aryl coupling reaction. This reaction is coverage dependent, with a lower rate at higher initial coverage; this behaviour is attributed to a stabilization of Ni-TTBPBP in the ordered islands at higher coverage.

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Section: Resultscontrasting

confidence: 72%

Self-assembly and coverage dependent thermally induced conformational changes of Ni(ii)-meso-tetrakis (4-tert-butylphenyl) benzoporphyrin on Cu(111)

Zhang

Lepper

Stark

et al. 2015

Phys. Chem. Chem. Phys.

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“…Under these conditions, the cyclodehydrogenation of 1a forms perylene and the five-membered ring product 5 . 33 For improving the yield of the desired perylene derivative ( 2d ), different reaction conditions were assessed by changing the temperature and the equivalents of K ( Table S6 ).…”

Section: Results and Discussionmentioning

confidence: 99%

1-Substituted Perylene Derivatives by Anionic Cyclodehydrogenation: Analysis of the Reaction Mechanism

et al. 2022

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Perylene derivatives constitute a promising class of compounds with technological applications mainly due to their optoelectronic properties. One mechanism proposed to synthesize them, starting from binaphthyl derivatives, is anionic cyclodehydrogenation (under reductive conditions). However, the scope of this reaction is limited. In the present study, we report a theoretical and experimental analysis of this particular reaction mechanism for its use in the synthesis of 1-substituted perylenes. Different substituents at position 2 of 1,1′-binaphthalene were evaluated: −OCH 3 , −OSi(CH 3 ) 2 C(CH 3 ) 3 , and −N(CH 3 ) 2 . Based on density functional theory (DFT) calculations on the proposed mechanism, we suggest that the cyclization takes place from binaphthyl dianion instead of its radical anion. This dianion has an open-shell diradical nature, and this could be the species that was detected by EPR in previous studies. The O -substituted derivatives could not afford the perylene derivatives since their radical anions fragment and the necessary binaphthyl dianion could not be formed. On the other hand, 49% of N,N -dimethylperylen-1-amine was obtained starting from the N -substituted 2-binapthyl derivative as a substrate, employing a simpler experimental methodology.

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“…[34] Aaron Amick and Sara Martin (Washington College, Maryland) have discovered that an external radical source (hexane) greatly facilitates cyclodehydrogenation of polycyclic aromatic hydrocarbons (PAHs) under FVP conditions. [35] David Lupton and his co-workers (Monash) describe in a Communication that subjection of N-methyl carbazolone allyl carbonates bearing a propargyl side chain to Pd[0] catalysis leads to the formation of enantioenriched g-lactones, rather than the expected products of decarboxylative allylation. [36] Jia Cao and Patrick Perlmutter (Monash) report a facile, microwave-assisted, solvent-free synthesis of iodides from tosylates.…”

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confidence: 99%

Roger F. C. Brown Memorial Issue

Wentrup

2014

Aust. J. Chem.

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Use of External Radical Sources in Flash Vacuum Pyrolysis to Facilitate Cyclodehydrogenation Reactions in Polycyclic Aromatic Hydrocarbons

Cited by 4 publications

References 45 publications

Self-assembly and coverage dependent thermally induced conformational changes of Ni(ii)-meso-tetrakis (4-tert-butylphenyl) benzoporphyrin on Cu(111)

Self-assembly and coverage dependent thermally induced conformational changes of Ni(ii)-meso-tetrakis (4-tert-butylphenyl) benzoporphyrin on Cu(111)

1-Substituted Perylene Derivatives by Anionic Cyclodehydrogenation: Analysis of the Reaction Mechanism

Roger F. C. Brown Memorial Issue

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