The Chemistry of 1,3,5-Triazacyclohexane Complexes. 6.(1) Synthesis and Characterization of the Cobalt(II) Methoxide Core {Co(3)(OMe)(4)}(2+).
We report the synthesis and characterization of the first eta(3)-1,3,5-trimethyl-1,3,5-triazacyclohexane (Me(3)TAC) alkoxo complexes. Dehydration of [Co(H(2)O)(6)](X)(2) with 2,2-dimethoxypropane or HC(OMe)(3) and subsequent treatment with Me(3)TAC results in the formation of the methoxo cube fragment clusters [{(Me(3)TAC)Co}(3)(OMe)(4)](X)(2) (X = B(C(6)F(5))(4) (2a) and B(m-C(6)H(3)(CF(3))(2))(4) (2b)). 2a crystallizes in the triclinic space group P&onemacr; (a = 13.857(2) Å, b = 16.843(3) Å, c = 19.318(2) Å, alpha = 79.23(2) degrees, beta = 76.855(13) degrees, gamma = 70.10(2) degrees, Z = 2) and 2b in the monoclinic space group P2(1) (a = 12.710(3) Å, b = 23.251(3) Å, c = 18.702(4) Å, beta = 101.16(2) degrees, Z = 2). The cations contain a {Co(3)(OMe)(4)} cube fragment core with an eta(3)-Me(3)TAC bonded to each cobalt atom. Me(3)TAC is bonded unsymmetrically due to hydrogen-bonding interactions with the anions. This broken symmetry can also be observed as solvent-, anion-, and H/D isotope-dependent splitting of the signals in (1)H and (2)H NMR. A byproduct of the reaction is the protonated Me(3)TAC. The analogous monoacid adduct Me(3)TAC.HCl has been characterized by X-ray crystallography (orthorhombic space group Pbca, a = 11.0366(9) Å, b = 12.2986(6) Å, c = 13.9949(7) Å, Z = 8).
Köhn
Randolf D.
RD
Institut für Anorganische und Analytische Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, D-10623 Berlin, Germany, and Institut für Anorganische und Allgemeine Chemie, Humboldt Universität zu Berlin, Hessische Strasse 1-2, D-10115 Berlin, Germany.
Haufe
Matthias
M
Kociok-Köhn
Gabriele
G
Filippou
Alexander C.
AC