Aspects of the chemistry of donor solvent coal dissolution reactions. The reduction of benzophenone and the disproportionation of benzhydrol in hydrocarbon solvents at high temperature

Choi, Chol Yoo; Stock, Leon M.

doi:10.1021/jo00190a005

Cited by 19 publications

(13 citation statements)

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“…The existence of condensation (route IV) was retrieved from experiments with anthracene only, to give both 9-(1‘- and 2‘-naphthyl)anthracene when starting with the 1-chloronaphthalene (see Figure ). A similar condensation-type reaction was reported by Stein for pyrocondensation of anthracene and anthracene/naphthalene mixtures . The mechanism is thought to involve a biradical intermediate from the addition of chloronaphthalene to anthracene, preferably at the 2-naphthyl and 9-anthracene positions, followed by HCl elimination (see Figure ).…”

Section: Resultssupporting

confidence: 67%

Study of Hydrogen Shuttling Reactions in Anthracene/9,10-Dihydroanthracene−Naphthyl-X Mixtures

Arends

1996

Energy Fuels

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In a matrix of anthracene (An) and 9,10-dihydroanthracene (AnH2) (1:1) between 350 and 400 °C in pressurized liquid systems, the rates and mechanisms have been studied for desubstitution of a number of aromatic compounds: naphthyl-X, with X = Cl, Br, F, D, CH3, NH2, CHCH2, OCH3, OH, Ph, C(O)CH3. It appears that for these compounds hydrogen transfers via radical hydrogen transfer (RHT) by 9,10-dihydroanthracenyl radicals (9-AnH•) or reverse radical displacement (RRD) with 9,10-dihydroanthracene are the major desubstitution pathways. However, for bromo- and chloronaphthalene, desubstitution is much faster and naphthyldihydroanthracenes and naphthylanthracenes are the main products. In these cases Radical displacement (RD) by 9-AnH• is the predominant route. Also, condensation between An and naphthyl-X is noticed. During these experiments the hydrogenation of aromatic rings was observed as well: anthracene → 1,2,3,4-tetrahydroanthracene and naphthalene → tetralin. This process has been studied by employing naphthalene-d 8. The rate of H/D exchange appears to be twice as fast as hydrogenation in the naphthalene molecule. A thermodynamic and kinetic rationale is presented to explain the change in mechanism as a function of the substituent.

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Section: Resultssupporting

confidence: 67%

Study of Hydrogen Shuttling Reactions in Anthracene/9,10-Dihydroanthracene−Naphthyl-X Mixtures

Arends

1996

Energy Fuels

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“…High-boiling hydrocarbons have been used by others as hydrogen donors for the reduction of carbonyl compounds, at temperatures around 400 °C. 11,12 However, in contrast with the present work (which employed considerably lower temperatures), a,b-unsaturated carbonyl compounds were selectively hydrogenated at the carbon-carbon double bond, while the carbonyl group remained intact. 11 Herein, cyclohexanone and acetophenone afforded cyclohexanol and 1-phenylethanol, respectively (entries 5 and 6).…”

contrasting

confidence: 81%

Uncatalysed hydrogen-transfer reductions of aldehydes and ketones

Bagnell¹,

Strauss²

1999

Chem. Commun.

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“…Furthermore, the products also contain reactive oxygen functional groups (ketone, alcohol, phenol) that can become involved in additional thermally induced, retrogressive reactions (formation of complex cyclic ethers, adduction to aromatics, reduction to diphenylmethanes, etc. ). , This research suggests that related chemistry for aryl alkyl ethers in low-rank coals may contribute to the difficulty experienced in their thermochemical processing.…”

Section: Discussionmentioning

confidence: 83%

Pyrolysis of Silica-Immobilized Benzyl Phenyl Ether: Competing Radical Rearrangement Pathways under Restricted Diffusion

et al. 1998

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Pyrolysis studies of silica-immobilized benzyl phenyl ether (≈PhOCH2Ph or ≈BPE), a model for related ether structures in fuel resources, have been conducted at 275−325 °C to examine the impact of restricted mass transport on the pyrolysis mechanism compared with previous studies in fluid phases. Significant rearrangement chemistry is observed for ≈BPE occurring through two competitive free-radical pathways that are both promoted by the diffusional constraints. One path involves recombination of incipient benzyl and surface-bound phenoxy radicals to form benzylphenol isomers, 10. The second, previously unreported rearrangement path for ≈BPE involves a 1,2-phenyl shift in an intermediate radical, ≈PhOCH·Ph, leading to formation of benzhydrol (8) and benzophenone (9) as principal products. The rearrangement products 8−10 typically account for ca. 50% of the pyrolysis products. However, the path selectivity is a sensitive function of ≈BPE surface coverage and the presence of spacer molecules that either facilitate or hinder hydrogen atom transfer steps on the surface.

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Aspects of the chemistry of donor solvent coal dissolution reactions. The reduction of benzophenone and the disproportionation of benzhydrol in hydrocarbon solvents at high temperature

Cited by 19 publications

References 1 publication

Study of Hydrogen Shuttling Reactions in Anthracene/9,10-Dihydroanthracene−Naphthyl-X Mixtures

Study of Hydrogen Shuttling Reactions in Anthracene/9,10-Dihydroanthracene−Naphthyl-X Mixtures

Uncatalysed hydrogen-transfer reductions of aldehydes and ketones

Pyrolysis of Silica-Immobilized Benzyl Phenyl Ether: Competing Radical Rearrangement Pathways under Restricted Diffusion

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