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Artigo Acesso aberto Revisado por pares

Christophe Audouard, Igor Barsukov, John Fawcett, Gerry A. Griffith, Jonathan M. Percy, Stéphane Pintat, Clive A. Smith,

A (bromodifluoromethyl)alkyne has been deployed in a stereoselective route to difluorinated aldonic acid analogues, in which a Sharpless asymmetric dihydroxylation reaction and diastereoisomer separation set the stage for phenyl group oxidation.

Tópico(s): Asymmetric Synthesis and Catalysis

2004 - Royal Society of Chemistry | Chemical Communications

Jornais Acesso aberto

G. W. PEPYS-GOODCHILD, A.M.I.M.E., F.R.S.A., VALENTINE KNAPP. Treasurer., RICHARD MORRIS., J. B. WHITMORE., ASSHETON POWNALL. House of Commons, July 22., HUGH WALPOLE. 90, Piccadilly, W., DOROTHEA FAIRBRIDGE. Ladies' Empire Club, 69, Grosvenor-street, W., July 18., (FROM A CORRESPONDENT)., CALLISTHENES., JULIUS L. F. VOGEL., TAXPAYER., RONALD A. HOPWOOD, Vice-Admiral (Retired). 8, Eaton-terrace, S.W.1, July 21., CIVIS LONDON:,

... Societies For Equal Citizenship. Tributes To Dame Millicent Fawcett., The Prince At Kimberley. Visit To Diamond Mines., Education Vote. Lord Eustace Percy's Policy., Mr. Pember Reeves And Greece., Duke ...

1925 - Gale Group | TDA

Artigo Revisado por pares

Christophe Audouard, John Fawcett, Gerry A. Griffiths, Jonathan M. Percy, Stéphane Pintat, Clive A. Smith,

4-Deoxy-4,4-difluoro-glycosides have been synthesised for the first time via a direct sequence involving ring-closing metathesis and indium-mediated difluoroallylation with 1-bromo-1,1-difluoropropene in water. Two protecting group strategies were explored, one to allow protection of the primary C-6 hydroxyl group throughout the sequence, while the second was intended to allow deprotection after RCM and before dihydroxylation. The benzyl ether could be used in the first role, and pivaloyl is effective ...

Tópico(s): Fluorine in Organic Chemistry

2004 - Royal Society of Chemistry | Organic & Biomolecular Chemistry

Artigo Acesso aberto Revisado por pares

John Fawcett, Gerry A. Griffiths, Jonathan M. Percy, Stéphane Pintat, Clive A. Smith, Neil S. Spencer, E. Uneyama,

Difluorinated cyclooctenones, synthesised using RCM, can be used as templates for stereoselective oxidative transformations to products that undergo transannular reactions to afford conformationally-locked analogues of 2-deoxy-2,2-difluorosugars with different stereochemical relationships between the C-2 and C-3 hydroxyl groups.

Tópico(s): Oxidative Organic Chemistry Reactions

2004 - Royal Society of Chemistry | Chemical Communications

Jornais Acesso aberto

FROM OUR CORRESPONDENTS., GALLOWAY., A DUNDALK ELECTOR., CATHERINE GLADSTONE., CHARLES WHITE, H. R. WILLIAMS AND Co, HAIG AND Co, Our Dublin Correspondent,

... PARISH.-Yesterday, in the, London Water Companies., Mr. Fawcett At Hackney., ... Edward Percy Rostrams, de-, At Southwark, Charles John Holmes, alias ...

1880 - Gale Group | TDA

Artigo Revisado por pares

John Fawcett, Gerry A. Griffith, Jonathan M. Percy, E. Uneyama,

Topologically mobile difluorinated cyclooctenones undergo rapid, high-yielding, and completely stereoselective epoxidations with methyl(trifluoromethyl)dioxirane. The epoxides resist conventional hydrolysis but react smoothly in basic media under microwave irradiation to afford unique hemiacetals and hemiaminals in good yield. [reaction: see text]

Tópico(s): Carbohydrate Chemistry and Synthesis

2004 - American Chemical Society | Organic Letters

Artigo

Elizabeth Bush,

... Quest for Z: The True Story of Explorer Percy Fawcett and a Lost City in the Amazon by ... Quest for Z: The True Story of Explorer Percy Fawcett and a Lost City in the Amazon; written ... Reviewed from galleys R Gr. 3–5 For Percy Fawcett, born into a family of British adventurers, a ...

Tópico(s): History of Science and Medicine

2017 - Johns Hopkins University Press | Bulletin of the Center for Children's Books./Bulletin of the Center for Children's Books

Jornais Acesso aberto

EDWARD TROUP., MILLICENT GARRETT FAWCETT, President. BERTHA MASON, Treasurer. EDITH DIMOCK, Hon. Secretary. Parliament Chambers, S.W., June 4., PERCY DUNN., COULSON KERNAHAN., ERNEST G. PRETYMAN., PACIFICUS., HENRY CHAPLIN. Stafford House, St. James's, S.W., June 3.,

Births. Marriages. Deaths. Classified Advertising: Cautions And Notices., Shipping., Household Servants Wanted., Partnerships, Investments, Business Opportunities, & ...

1910 - Gale Group | TDA

Artigo Revisado por pares

Carolyn Dean,

... of Stone, op cit, pp 112–121 26. Percy Harrison Fawcett, Exploration Fawcett, Brian Fawcett, ed, Hutchinson Books, London, ...

Tópico(s): Indigenous Cultures and History

2011 - Routledge | Third Text

Jornais Acesso aberto

"J. C. SHERBROOKE.", ETTIE SAYER., LEONARD DARWIN, P. VON FLEISCHL, S. GOTTO, P. H. FAWCETT., JAMES PARKER., J. A. GRANT., ALFRED C. DEWAR., A. U., H. PERCY HARRIS., ERNEST W. MUNTON., CHARLES BATHURST., WYNDHAM A. BEWES., GEORGE HOLLOWAY., R.10, 796., F. W. WILLCOX., THOS. HENNELL, FROM ENGINEERING CORRESPONDENTS AT HOME AND ABROAD., STEPHEN SELLON.,

Births. Marriages. Deaths. Classified Advertising: County Of London., Theatres, &c., Charities, &c., Mescellaneous Companies., 'Allenburys' Diet, Shipping., ...

1912 - Gale Group | TDA

Artigo Acesso aberto Revisado por pares

Patrick Crowley, John Fawcett, Gerry A. Griffith, A.C. Moralee, Jonathan M. Percy, V. Salafia,

A difluorinated dienophile underwent cycloaddition reactions with a range of furans to afford cycloadducts which could be processed regio- and stereoselectively via episulfonium ions, generated by the reaction between their alkenyl groups and phenylsulfenyl chloride. The oxabicyclic products were oxidised to the phenylsulfonyl level and ring opened via E1(C)B or reductive desulfonative pathways to afford, ultimately, difluorinated cyclohexene or cyclohexane polyols.

Tópico(s): Organic Chemistry Cycloaddition Reactions

2005 - Royal Society of Chemistry | Organic & Biomolecular Chemistry

Artigo Revisado por pares

Patrick Crowley, John Fawcett, Benson M. Kariuki, A.C. Moralee, Jonathan M. Percy, V. Salafia,

Phenylsulfenyl chloride reacts with racemic endo Diels-Alder adduct 4 (DEC = CONEt(2)) to afford lactone 8, which can be reduced and protected in a series of high-yielding steps. Key sulfone 10 can be ring opened under strong base conditions to afford vinyl sulfone 11. Attempted desulfonation resulted in the formation of a monofluoroalkene, but a direct desulfonation/eliminative ring opening with strain relief delivered highly functionalized monocyclic species 16. [reaction: see text]

Tópico(s): Synthetic Organic Chemistry Methods

2002 - American Chemical Society | Organic Letters

Artigo Revisado por pares

Christophe Audouard, John Fawcett, Gerry A. Griffith, E. Kerouredan, Afjal H. Miah, Jonathan M. Percy, Hongli Yang,

Direct precursors to analogues of pentopyranoses, 6-deoxyhexoses, and hexoses, in which a CF(2) center replaces the pyranose oxygen, have been synthesized rapidly from trifluoroethanol. A simple scaleable allylation reaction delivers ethers which undergo dehydrofluorination/metalation, followed by addition to either acrolein or cinnamaldehyde, to afford allylic alcohols. Fluorine-assisted [3,3]-rearrangement followed by reduction with sodium borohydride delivers diols, which undergo RCM smoothly ...

Tópico(s): Marine Sponges and Natural Products

2004 - American Chemical Society | Organic Letters

Artigo Acesso aberto Revisado por pares

Andrea Arany, Patrick Crowley, John Fawcett, Michael B. Hursthouse, Benson M. Kariuki, Mark E. Light, A.C. Moralee, Jonathan M. Percy, V. Salafia,

A difluorodienophile, synthesised using a Stille coupling reaction underwent tin(IV)-catalysed cycloaddition with three furans to afford oxa[2.2.1]bicycloheptenes in good yield. Reduction of ester and carbamate carbonyl groups and diol protection as the acetonide set the stage for palladium-catalysed hydrostannylation in two cases. Treatment of the stannanes with methyllithium triggered ring-opening to afford highly-functionalised difluorinated cyclohexenols which could be deprotected to afford ( ...

Tópico(s): Synthesis and Biological Evaluation

2004 - Royal Society of Chemistry | Organic & Biomolecular Chemistry

Jornais Acesso aberto

Richard Scott, J.W. Fawcett, Forrest Studebaker, Ian Chipperfield, Brian Lipkin, Fred Gottheil, S. Bhattacharyya, T.C. Worstall, Peter Sisson, Ahmet Ersoy, Percy Mistry, T.E. Bostock, K.G. Wormsley, Mark Beattie, Nicolas Photiades, Diarmuid Baigrie, Barry Weightman, Paul Volcker,

The Economist Union Bank Of Switzerland The Economist A weighty World Bank The Economist Pacific ways A forgotten prisoner Executive Focus Thatcher's ...

1991 - Gale Group | The Economist

Artigo Acesso aberto Revisado por pares

John Fawcett, A.C. Moralee, Jonathan M. Percy, V. Salafia, Mark A. Vincent, Ian H. Hillier,

Difluorinated analogues of (hydroxymethyl)conduritols can be synthesised from selected furans and a difluorinated dienophile in two reaction steps.

Tópico(s): Carbohydrate Chemistry and Synthesis

2004 - Royal Society of Chemistry | Chemical Communications

Jornais Acesso aberto

From Our Golf Correspondent, From Our Billiards Correspondent, From Our Special Correspondent, From Our Rackets Correspondent, From Our Boxing Correspondent, From Our Racing Correspondent, From Our Newmarket Correspondent, Our Parliamentary Correspondent, From Our Chess Correspondent, From Our Correspondent, By Our Motoring Correspondent, From Our Insurance Correspondent, From Our Own Correspondent, From Our Parliamentary Correspondent, Hesketh Bell., Anne Fremantle., Edgar Sanders., Mr. G. A. Tomlin, E. L. Douglas Fowles., A. H. Taylor., Joseph Balogh., H. G. Griffin, From Our Philatelic Correspondent, From Our Aeronautical Correspondent, By Callisthenes, From Our Diplomatic Correspondent, M. P., From Our Paris Correspondent, Harold Macmillan., D. G. Williams., R. B. Mowat., From Our Bridge Correspondent, From A Correspondent, From A Textile Correspondent, Lord Snell, By Reginald W. Bell, By Sir Gwilym Gibbon, Lord Dickinson, Herbert Morrison, Sir Harold Webbe, By Our Architectural Correspondent, George Lansbury, By Dr. B. M. Allen, By Sir Robert Pickard, By W. J. Pincombe, By Dr. F. H. Spencer, By J. M.. Ritchie., Lord Dawson Of Penn, By Sir William J. Collins, From Our Medical Correspondent, From A Special Correspondent, By Sir Lawrence Chubb, By Charles Latham, Sir Samuel Gluckstein, By Sir George W. Humphreys, By Sir Isidore Salmon, By John Betts, By P. Elton Longmore, By Sir Cyril Hurcomb, By The Right Hon. Lord Ashfield, , By Sir David Milne-Watson, By Colonel Sir William Prescott, Lord Ritchie, By Sir Chartres Biron, By Sir Wyndham Deedes, By John J. Clarke,

... Anderson On Civilian Defence, Importance Of Exports Sir Percy Bates On British ... Colonel Fawcett's Fate Reported Discovery Of Skeletons, Riots In ...

1939 - Gale Group | TDA

Artigo Revisado por pares

Christine Elowitt,

... movie tells the true story of British explorer Percy Fawcett’s career as a military man and explorer. ...

Tópico(s): History of Science and Natural History

2017 - University of Hawaii Press | Yearbook - Association of Pacific Coast Geographers

Artigo Revisado por pares

Marc Angenot,

... disparition en Amérique du Sud de l'explorateur Percy Fawcett dans les années 1920, etc. Cet article se ...

Tópico(s): Comics and Graphic Narratives

2010 - Presses de l'Université de Montréal | Études françaises

Artigo Acesso aberto Brasil Produção Nacional

Deborah Lavorato Leme,

... um bilhete de autoria atribuída ao explorador britânico Percy Harrison Fawcett, escrito durante sua última expedição ao Brasil em ...

Tópico(s): Historical Geography and Geographical Thought

2021 - | LaborHistórico

Jornais Acesso aberto

Our Own Correspondent., A Correspondent.,

... Of Appeal., Queen's Bench Division. Bowyer V. Percy Supper Club., Police.. ... late MR. FAWCETT,. Stock Exchange Tables: Foreign Markets. New York Stock ...

1893 - Gale Group | TDA

Artigo Acesso aberto

André Reyes Novaes,

... indígenas nos mapeamentos amazônicos conduzidos pelo explorador britânico Percy Harrison Fawcett. Atuando como engenheiro chefe da comissão boliviana de ...

Tópico(s): Colonialism, slavery, and trade

2020 - | Terra Brasilis