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Proton-catalyzed hydrogenation of a d(8) Ir(I) complex yields a trans Ir(III) dihydride.

ABSTRACT: Hydrogenation of the (PONOP)Ir(I)CH(3) complex [PONOP = 2,6-bis(di-tert-butylphosphinito)pyridine] yields the unexpected trans-dihydride species (PONOP)IrCH(3)(H)(2). Mechanistic investigations have revealed that this reaction proceeds via proton-catalyzed H(2) cleavage, a pathway that circumvents the intermediacy of the typically invoked cis-dihydride isomer. Protonation yields the cationic (PONOP)Ir(CH(3))(H)(+) complex, which is then trapped by H(2) to yield an eta(2)-H(2) complex. Deprotonation of this species yields the trans-dihydride. Intermediates in the proposed pathway have been confirmed by independent low-temperature syntheses and spectroscopic observations.

SUBMITTER: Findlater M

PROVIDER: S-EPMC2858392 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Proton-catalyzed hydrogenation of a d(8) Ir(I) complex yields a trans Ir(III) dihydride.

Findlater Michael M Bernskoetter Wesley H WH Brookhart Maurice M

Journal of the American Chemical Society 20100401 13

Hydrogenation of the (PONOP)Ir(I)CH(3) complex [PONOP = 2,6-bis(di-tert-butylphosphinito)pyridine] yields the unexpected trans-dihydride species (PONOP)IrCH(3)(H)(2). Mechanistic investigations have revealed that this reaction proceeds via proton-catalyzed H(2) cleavage, a pathway that circumvents the intermediacy of the typically invoked cis-dihydride isomer. Protonation yields the cationic (PONOP)Ir(CH(3))(H)(+) complex, which is then trapped by H(2) to yield an eta(2)-H(2) complex. Deprotonat ...[more]

PMID: 20232913

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