New diamondoid-like [Cu3B(μ-O)6] core self-assembled from Bis-Tris biobuffer for mild hydrocarboxylation of alkanes to carboxylic acids

Centro de Química Estrutural, Complexo I, Instituto Superior Técnico, TU Lisbon, Avenida Rovisco Pais, 1049-001, Lisbon, Portugal.
Dalton Transactions (Impact Factor: 4.2). 06/2011; 40(24):6378-81. DOI: 10.1039/c1dt10421g
Source: PubMed


The new tricopper(II) complex [Cu(3)(μ(3)-BO)(H(3)L)(3)][BF(4)]·2H(2)O (1) with an unprecedented diamondoid-like [Cu(3)B(μ-O)(6)] core has been easily generated by self-assembly in an aqueous medium from Cu(NO(3))(2), NaBF(4), NaOH and Bis-Tris (H(5)L) biobuffer, (HOCH(2))(3)CN(CH(2)CH(2)OH)(2). Compound 1 efficiently promotes the mild single-pot hydrocarboxylation, by CO and H(2)O, of various linear and cyclic C(n) (n = 2-8) alkanes into the corresponding C(n+1) carboxylic acids.

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    ABSTRACT: In methanol under solvothermal conditions, we show how the nuclearity of the complex can be tuned from a monomer [CrIII(H3L)Cl] (1) to a tetramer [CrIII4(H2L)4] (2) with an unusual twisted {M4O4} core topology {Bis–tris, H5L = (HOCH2CH2)2NC(CH2OH)3}. The magnetic data for 2 can be fitted to a simple 1J model with J = − 20.25(5) cm− 1.
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