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Thermodynamically Controlled, Dynamic Binding of Diols to a 1,2-BN Cyclohexane Derivative.

ABSTRACT: The reversible covalent binding of diols to an N-Bn 1,2-BN cyclohexane has been studied by 11B and 1H NMR spectroscopy and single-crystal X-ray diffraction analysis. The activation barrier for the reversible B-N Lewis acid-base interaction has been measured by variable-temperature NMR with bound (2R,3R)-(-)-2,3-butanediol (Tc = -40 °C, ?G‡ = 11.2 ± 0.2 kcal mol-1). Deuterium labeling experiments demonstrate that ligand exchange is reversible and rapid at room temperature, and competitive binding studies establish diol association as a thermodynamically controlled process.

SUBMITTER: Harlow GP

PROVIDER: S-EPMC4364440 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Thermodynamically Controlled, Dynamic Binding of Diols to a 1,2-BN Cyclohexane Derivative.

Harlow Gregory P GP Zakharov Lev N LN Wu Gang G Liu Shih-Yuan SY

Organometallics 20130101 22

The reversible covalent binding of diols to an N-Bn 1,2-BN cyclohexane has been studied by 11B and 1H NMR spectroscopy and single-crystal X-ray diffraction analysis. The activation barrier for the reversible B-N Lewis acid-base interaction has been measured by variable-temperature NMR with bound (2R,3R)-(-)-2,3-butanediol (Tc = -40 °C, ΔG‡ = 11.2 ± 0.2 kcal mol-1). Deuterium labeling experiments demonstrate ...[more]

PMID: 25798022

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