Mononuclear nine-coordinate

The reaction products of 2,2 -bipyrimidine (bpm), P-diketones, and lanthanide ions demonstrated the diverse nuclearity and dimensionality. As stated in the last section, dinuclear eight-coordinate [Ln2(P-diketonate)6(bpm)] could be formed [78, 79]. Zucchi et al. [26a] reacted Nd(N03)3 with bpm to afford the mononuclear nine-coordinate adduct [Nd(N03)3(bpm)(Me0H)2], while reactions of hydrated NdCb and various P-diketonates in the presence of bpm gave the binuclear nine-coordinate compounds [ Nd(L )3(THF) 2([JL-bpm)] (see Figure 2.46) and [ Nd(L )3(MeOH) 2([r-bpm)]-bpm (see Figure 2.47) and the one-dimensional coordination polymer [Nd(L )3(p,-bpm)-MeOH]oo (4-MeOH) (see Figures 2.48 and 2.49). Other groups have also reported the one-dimensional arrays [Ln(L )3(p.-bpm)]co (Ln = Eu [80], Gd, and Nd [75]. 

The only complexes of lanthanum or cerium to be described are [La(terpy)3][C104]3 175) and Ce(terpy)Cl3 H20 411). The lanthanum compound is a 1 3 electrolyte in MeCN or MeN02, and is almost certainly a nine-coordinate mononuclear species the structure of the cerium compound is not known with any certainty. A number of workers have reported hydrated 1 1 complexes of terpy with praseodymium chloride 376,411,438), and the complex PrCl3(terpy)-8H20 has been structurally characterized 376). The metal is in nine-coordinate monocapped square-antiprismatic [Pr(terpy)Cl(H20)5] cations (Fig. 24). Complexes with a 1 1 stoichiometry have also been described for neodymium 33, 409, 411, 413, 417), samarium 33, 411, 412), europium 33, 316, 411, 414, 417), gadolinium 33, 411), terbium 316, 410, 414), dysprosium 33, 410, 412), holmium 33, 410), erbium 33, 410, 417), thulium 410, 412), and ytterbium 410). The 1 2 stoichiometry has only been observed with the later lanthanides, europium 33, 411, 414), gadolinium, dysprosium, and erbium 33). 

Mononuclear [Yb(02CCCl3)3.(terpy).MeOH] contains coordinated methanol and two uniden-tate carboxylates and one bidentate carboxylate affording eight coordinate ytterbium and [Ln(02CCCl3)3 (terpy) (H2O)] (Ln = La-Nd) are dimeric with nine-coordinate lanthanides. A compound [Lu(02CCCl3)3 (terpy) (H2O)] contains both the foregoing geometries. 

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