Acceptorless, intramolecular, alkyl dehydrogenation in the solid-state in a rhodium phosphine complex; reversible uptake of three equivalents of H(2) per molecule

Journal article

Addition of H2 to the phosphine alkene ligated complex [Rh(dppe)(PCyp2Cyp′)][BArF4] 1 (Cyp = cyclo-C5H 9; Cyp′ = cyclo-C5H7, ArF = 3,5-(CF3)2C6H3) in the solid state results in hydrogenation of the alkene and uptake of two further equivalents of H2 to afford the dihydride-dihydrogen complex [Rh(dppe)(PCyp 3)(H)2(η2-H2)][BArF4] 2. Placing 2 under a vacuum or argon results in sequential loss of H2 and dehydrogenation of one of the cyclopentyl rings to reform 1. The hydrogenation-dehydrogenation cycle has been repeated 5 times without apparent degradation and has been followed by solid-state 31P{1H} NMR spectroscopy. Intermediates on this process have been trapped using acetonitrile to give stable complexes that have been characterised in solution. We have previously shown that this hydrogenation-dehydrogenation process also happens in the solution-state; and evidence is presented that shows that, apart from a subtle difference, the same overall transformation occurs in the solid-state. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.

Authors: Douglas, T; Weller, A

• Publication status: Published
• Journal: NEW JOURNAL OF CHEMISTRY
• Volume: 32
• Issue: 6
• Pages: 966-969
• Publication date: 2008-01-01
• DOI: 10.1039/b718615k
• EISSN: 1369-9261
• ISSN: 1144-0546
• Language: English