New Hydrogen Transfer Catalysts

✍ Scribed by Jens Morgenthaler; Christoph Rüchardt

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 458 KB
• Volume: 1999
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/(sici)1099-0690(199909)1999:9<2219::aid-ejoc2219>3.0.co;2-d

✦ Synopsis

The transfer of hydrogen from excess 9,10-dihydro-H-atom transfer from 4-7 to the acceptor (retrodisproportionation) and proceed by nonchain radical mechanisms. anthracene (DHA) to acceptors such as α-methylstyrene is catalyzed, i.e. occurs at temperatures in the range 200-260 This is supported by isotopic labelling and kinetic isotope effects, substituent and solvent effects, EPR spectroscopy of °C instead of 280-320 °C, when hydrocarbons with weaker C-H bonds than DHA, e.g. 6H-benzo[cd]pyrene (4), 7H-intermediate radicals, and by a comparison of the thermochemical and kinetic characteristics of these dibenzo[a,kl]anthracene (5), 4-methyl-7H-benzo[de]naphthacene (6) or 8H-dibenzo[b,fg]pyrene (7), are added to the reactions. reaction mixture. The reactions are initiated by bimolecular bound hydrogen atom from the donor to the acceptor in a [ ] Part 14: Ref. [13]