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Borane B-C Bond Cleavage by a Low-Coordinate Iron Hydride Complex and N-N Bond Cleavage by the Hydridoborate Product.

ABSTRACT: The iron(II) hydride dimers [L(R)Fe(?-H)(2)FeL(R)] (L(Me) = 2,4-bis(2,6-diisopropylphenylimino) pent-3-yl; L(tBu) = 2,2,6,6-tetramethyl-3,5-bis(2,6-diisopropylphenylimino)hept-4-yl) abstract hydrocarbyl groups from BR'(3) (R' = Et, Ph) to give L(R)FeR' and L(R)Fe(?-H)(2)BR'(2). Mechanistic studies with R = R' = Me are consistent with a process in which the hyride dimer opens one Fe-H bond, and subsequent B-H bond formation is concerted with dissociation of an Fe-H unit. Cleavage of boron-carbon bonds is likely to proceed at least in part from transient quaternary borate anions. In a separate bond-breaking reaction, L(Me)Fe(?-H)(2)BEt(2) reacts with N(2)H(4) to eject H(2) from the bridging hydrides and cleave the N-N bond in the diaminoborate complex L(Me)Fe(?-NH(2))(2)BEt(2). These novel bond-breaking reactions are facilitated by the low coordination number at the iron(II) center.

SUBMITTER: Yu Y

PROVIDER: S-EPMC2518744 | biostudies-literature | 2007

REPOSITORIES: biostudies-literature

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Borane B-C Bond Cleavage by a Low-Coordinate Iron Hydride Complex and N-N Bond Cleavage by the Hydridoborate Product.

Yu Ying Y Brennessel William W WW Holland Patrick L PL

Organometallics 20070101 13

The iron(II) hydride dimers [L(R)Fe(μ-H)(2)FeL(R)] (L(Me) = 2,4-bis(2,6-diisopropylphenylimino) pent-3-yl; L(tBu) = 2,2,6,6-tetramethyl-3,5-bis(2,6-diisopropylphenylimino)hept-4-yl) abstract hydrocarbyl groups from BR'(3) (R' = Et, Ph) to give L(R)FeR' and L(R)Fe(μ-H)(2)BR'(2). Mechanistic studies with R = R' = Me are consistent with a process in which the hyride dimer opens one Fe-H bond, and subsequent B-H bond formation is concerted with dissociation of an Fe-H unit. Cleavage of boron-carbon ...[more]

PMID: 18725998

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