Raymond S. Matthews
Durham University
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Featured researches published by Raymond S. Matthews.
Fuel | 1979
Keith D. Bartle; Ayla Çalimli; Derry W. Jones; Raymond S. Matthews; Aral Olcay; Hooshang Pakdel; Taner Tuǧrul
Abstract Fractions of Elbistan and Seyitomer (Turkish) lignites, extracted with supercritical toluene at 340 °C and 8 MPa, have been separated by solvent extraction and silica-gel chromatography. Analyses by n.m.r. and i.r. spectroscopies and other methods have been combined in structural-analysis schemes to yield information about the average molecule in aromatic extracts. Carbon aromaticities, f a , derived from 22.63 MHz 1 H-decoupled pulse Fourier-transform (PFT) 13 C-n.m.r. are more widely spread for Elbistan (0.34–0.56) than for Seyitomer (0.40–0.43), and are lower than for supercritical-gas (SCG) products from bituminous coals. 13 C-n.m.r. also reveals the presence of aromatic ether-O in polar fractions. Narrow aromatic signals in 100 MHz 1 H-n.m.r. spectra suggest the presence of single-aromatic-ring average structures. In the hexane-soluble aromatics, 27% (Elbistan) and 29% (Seyitomer) of the available sites are substituted by alkyI groups, some of which are at least eight carbon atoms long; the hexane-soluble polar and asphaltene/asphaltol fractions contain fewer such groups.
Applied Spectroscopy | 1980
Keith D. Bartle; Raymond S. Matthews; Jürgen Walter Stadelhofer
19F nuclear magnetic resonance chemical shifts are reported for the hexafluoroacetone adducts of 21 phenols commonly found in coal-derived mixtures. Signals for the adducts of certain phenols not readily separated by gas chromatography, such as the three cresols, are well resolved. Analysis of coal-derived phenol fractions by this procedure is simple and quantitative as long as 2,6-disubstituted compounds are not present, and the mixtures are not too complex.
Fuel | 1989
Alan Grint; Graeme Pieter Proud; Iain J.F. Poplett; Keith D. Bartle; S. Wallace; Raymond S. Matthews
Abstract Solid petroleum, ethylene-cracker, and coal tar pitches were characterized by 13 C cross-polarizationmagic-angle-spinning nuclear magnetic resonance spectroscopy (CP/MAS n.m.r.) and by dipolar dephasing. The relative numbers of carbon atoms were determined by peak synthesis of the dipolar dephased (DD) spectrum and of the difference spectrum between the CP/MAS and DD spectra. Spectra and derived structural information obtained in this way were in good agreement with high-resolution n.m.r. spectra of pitch in solution. Solid state n.m.r. is shown to be an attractive alternative to the recording of spectra of pitches in reactive solvents.
Journal of Fluorine Chemistry | 1980
Gerald M. Brooke; Raymond S. Matthews; Nigel S. Robson
Abstract 1,3,4,5,6,7,8-Heptafluoro-2-naphthyl prop-2-enyl ether (8) was isomerised in boiling xylene to 1,3,4,5,6,7,8-heptafluoro- 1-(prop-2-enyl)naphthalen-2-one (9). Photolysis of (9) gave 2,5,7-trifluoro-3,4-(tetrafluorobenzo)tricyclo[3.3.1.O 2,7 ]non-3- en-6-one (11) (by a [2 + 2] addition) and 1,2,7-trifluoro-3,4- (tetrafluorobenzo) tricyclo [3.3.1.O 2,7 ]non-3-en-8-one (12) (via an initial [3,5] photochemically-allowed sigmatropic shift). Pyrolysis of (9) at 455° also gave (11), while at 490°, both (9) and (11) gave 1-fluorovinyl 4,5,6,7,8-pentafluoro-1-naphthyl ketone (19).
Journal of Fluorine Chemistry | 1988
Gerald M. Brooke; Raymond S. Matthews
Abstract Pentafluoroaniline(1) and 1,3,4,5,6,7,8-heptafluoro-2-naphthylamine(2) react with acetophenone in tetralin at reflux temperature in the presence of anhydrous zinc chloride to give the 3 H -azepine derivatives 6,7,8,9-tetrafluoro-2,4,-diphenyl-3 H -1-benzazepine (5) and 6,7,8,9,10,11-hexafluoro-2,4,-diphenyl-3 H -napth[2,1-b]azepine (6) respectively, in addition to the Schiff bases (3) and (4), found previously. The self-condensation product of acetophenone, β-benzoyl-α-methylstyrene (“dypnone”), is an intermediate in the ring-forming reactions. The heterocycles (5) and (6) exhibit fluxional behaviour which at 297K is fast for (5) but slow for (6) on the NMR time-scale.
Journal of Organometallic Chemistry | 1987
Martin R. Bryce; Raymond S. Matthews
Abstract Alkylation reactions of 2,3-dihydro-2-mercapto-2,1,3-benzophosphadiazine-4(1H)-thione-2-sulphide are described; reaction with methyl iodide occurs sequentially to produce mono-, di- and tri-methylated derivatives. Reaction of 1,2-dihydro-1-methyl-2,4-bis(methylthio)-2,1,3-benzophosphadiazine with p-chloroaniline leads to a product formed by displacement of SMe groups both from carbon and phosphorous. Lawessons reagent reacts with o-aminobenzamide to yield 1,2-dihydro-2,4-bis(p-methoxyphenyl)-2,1,3-benzophosphadiazine-2-sulphide. Details of 13C and 31P NMR used to identify these compounds are discussed.
Journal of Fluorine Chemistry | 1991
Gerald M. Brooke; Raymond S. Matthews; Mary E. Harman; Michael B. Hursthouse
Abstract Pentafluorophenyl propynoate (8), prepared from sodium pentafluorophenate and propynoyl chloride, on flash vacuum pyrolysis through silica gave 4,5,6,7,8-pentafluoro-2H- cyclohepta[b]furan-2-one (9). Treatment of (9) with sodium methoxide in methanol at −70°C produced a mixture of the 4-methoxy-, 5-methoxy-, 6-methoxy-, 7-methoxy- and 8-methoxy-tetrafluoro-2H-cyclohepta[b]furan-2-one compounds (10), (11), (12), (13) and (14) in the ratio 11:18:8:19:44 respectively. Under more forcing conditions, the 4,8- and 5,8-dimethoxy-trifluoro-2H-cyclohepta[b]furan-2-one compounds (15) and (16) respectively were formed. X-ray crystallography identified the 8-methoxy derivative (14), whose fluorine nmr spectrum enabled key resonances to be identified in the parent (9) and subsequently allowed the structures of all the other products to be deduced.
Journal of The Chemical Society-perkin Transactions 1 | 1980
Gerald M. Brooke; Raymond S. Matthews; Nigel S. Robson
Vapour-phase thermolyses of 2,3,5,6-tetrafluoro-4-pyridyl prop-2-enyl ether and 2,4,5,6-tetrafluoro-3-pyridyl prop-2-enyl ether gave 2,4,5,7-tetrafluoro-3-azatricyclo[3.3.1.02,7]non-3-en-6-one (14) and 2,3,5,7-tetrafluoro-4-azatricyclo[3.3.1.02,7]non-3-en-6-one (21) respectively by internal Diets–Alder reactions of Claisen rearrangement intermediates. 4-Bromo-2,3,5-trifluoro-6-pyridyl prop-2-enyl ether gave 4-bromo-3,5-difluoro-3-prop-2-enyl-pyridine-2,6(1H, 3H)-dione (19) the product of hydrolysis of a Claisen intermediate. Compounds (14) and (21) underwent ready hydrolysis to the corresponding cyclic lactams, in which the ketonic carbonyl group at C-6 in both cases had also been converted into a gem-diol [compounds (15) and (22), respectively]. Hydrolytic cleavage of (22) followed by oxidative cleavage with periodic acid and reaction with diazomethane gave a trimethoxycarbonyl compound (25) containing a difluorocyclobutane ring.
Journal of Fluorine Chemistry | 1998
Raymond S. Matthews
Abstract Nucleophilic fluoride fluoro-dechlorination of four isoquinolines (5,6,7,8-tetrachloro-,3,5,6,7,8-pentachloro-,3,4,5,6,7,8-hexachloro- and 1,3,4,5,6,7,8-heptachloro-isoquinoline) led to the preparation of 15 new polychloropolyfluoro isoquinolines by reaction with caesium fluoride in DMSO at 100°C. The product from the perchloroisoquinoline was an inseparable mixture of C 9 Cl 7− n F n N where n is 1–3. The order of reactivity in 1,3,4,5,6,7,8-heptachloro-isoquinoline [10] to nucleophilic attack by fluoride was 1⪢6=7=8>3=5>4
Journal of Fluorine Chemistry | 1982
Robert N. Barnes; Richard D. Chambers; Raymond S. Matthews
Abstract The anion generated by addition of CsF to perfluoroaza-cyclohexene is very stable in sulpholane. Reaction of CsF with perfluoro-4-isopropylazacyclohexa-1,4-diene gives a less-stable anion and its behaviour with temperature is described.