- Bimolecular formation of radicals by hydrogen transfer, 15. New hydrogen transfer catalysts
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The transfer of hydrogen from excess 9,10-dihydroanthracene (DHA) to acceptors such as α-methylstyrene is catalyzed, i.e. occurs at temperatures in the range 200-260 °C instead of 280-320 °C, when hydrocarbons with weaker C-H bonds than DHA, e g. 6H-benzo
- Morgenthaler, Jens,Rüchardt, Christoph
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p. 2219 - 2230
(2007/10/03)
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- Improved Synthesis and Crystal Structure of 7H-Dibenzanthracen-7-one
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An improved synthetic method gives pure 7H-dibenzanthracen-7-one, C21H12O, in a higher yield than those reported so far.The crystal structure has been determined by X-ray analysis.The space group is Pn21a, with unit cell dimensions of a=23.325(5), b=14.149(3), c=3.986(1) A, and Z=4.The structure was solved by the direct method and refined by the block-diagonal least-squares method to an R value of 0.044.The molecule is greatly distorted from the planar conformation because of an intramolecular steric repulsion between the hydrogen atoms.
- Fujisawa, Shoi,Oonishi, Isao,Aoki, Junji,Ohashi, Yuji,Sasada, Yoshio
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p. 3356 - 3359
(2007/10/02)
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- Optical activity in the 1,1′-binaphthyl series. Energy barriers to racemisation of 8-substituted 1,1′-binaphthyls
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8-Methyl- and 8-hydroxymethyl-1,1′-binaphthyl have been synthesised in the optically active state, and their Arrhenius parameters and transition-state theory (Eyring) functions for racemisation in solution determined. Optically active 8-bromomethyl-1,1′-binaphthyl has also been prepared, but velocity constants for its racemisation could not be determined because it decomposes at the temperatures required. Optical stabilities of 1,1′-binaphthyl substituted in the 8-position by -CO2H, -CO2Me, -CH2·OH, and -CH3 are compared within the series, and with those of the corresponding 8,8′-disubstituted compounds and of 1,1′-binaphthyl itself.
- Cooke, Ann S.,Harris, Margaret M.
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p. 988 - 992
(2007/10/05)
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