VOLATILE DONOR-FUNCTIONALIZED ALKOXY DERIVATIVES OF LUTETIUM AND THEIR STRUCTURAL CHARACTERIZATION

Reaction of beta-functionalized alcohols of type HOCR(2)CH(2)do (1a, d o = OMe, R = Me; Ib, do = OMe, R =; Et; lc, do = NMe2, R = Me) with Ln [N(SiMe3)(3)](3) yields highly volatile (sublimation < 100 degrees C/1 0(-3) Torr) and n-hexane-soluble homoleptic alkoxide complexes [Ln(OCR (2)CH(2)do)(3)] (2a-d, Ln = Y, Lu). A single-crystal X-ray diffraction study of Lu(OCMe2CH2OMe)(3) (2a) revealed a dinuclear complex with si gnificantly polarized metal centers originating from asymmetrical liga nd association (triple-bridging). Unintentional employment of ''water- contaminated'' alcohol la resulted in the formation of n-hexane-solubl e 3 exhibiting a substantially increased sublimation temperature (>220 degrees C/10(-3) Torr). Crystallization of 3 affords single crystals 3a featuring the tetranuclear constitution Lu-4(O)(OH)(OCMe2CH2OMe)(9) . 3a represents an unprecedented lanthanide alkoxide comprising both o xo and hydroxo units in addition to alkoxide ligands. The Lu4O15-core structure of 3a adopts a ''butterfly'' rather than a tetrahedral geome try. Potentially tridentate alcohols HOCtBu(CH(2)OiPr)(2) (4) and HOCi Pr2CH(2)OCH(2)OMe (5) afford alkoxide complexes ''Nd(OR)(3)'' (6, 7) o f reduced volatility. 2a crystallizes from n-hexane at ambient tempera ture in space group P2(1)/n with a = 13.510(1) Angstrom, b = 15.130(1) Angstrom, c = 38.953(4) Angstrom, beta = 93.11(1)degrees, V = 7950 An gstrom(3), and Z = 8. Least-squares refinement of the model based on 1 1 747 reflections (I > 2.0 sigma(1)) converged to a final R = 3.5%. 3a crystallizes from rt-hexane at -35 degrees C in space group Cc with a = 21.63(1) Angstrom, b = 14.49(3) Angstrom, c = 21.04(2) Angstrom, be ta = 109.70(3)degrees, V = 6209 Angstrom(3), and Z = 4. Least-squares refinement of the model based on 6057 reflections (I > 3.0 sigma(I)) c onverged to a final R = 6.7%.