Pentamethyldisilylmethyl derivatives of the transition metals, LMCH2SiMe2SiMe3 [LM = (η5-C5R5)M(CO)nn−, M = Fe, W, R = H, Me, n = 2, 3; (η5-C9H7)Fe(CO)2−; (η5-C5 H5)2MCl−, M = Ti, Zr, Hf]

Synthesis, Structure, and Fluxional Behavior of Base-Stabilized Silyl(silylene)tungsten Complexes

“…The trans geometry of 1a is attributable to the steric repulsion between the silyl group and the HMPA-coordinated silylene ligand. A similar trans configuration was commonly observed in phosphine-substituted silyltungsten complexes of the type CpW(CO) 2 (PR 3 )SiR‘ 3 .…”

“…The tungsten−silylene bond (W−Si(1) 2.481(3) Å) in 1a is significantly shorter than that of the tungsten−silyl bond (W−Si(2) 2.553(3) Å) in the same complex and those of structurally similar alkylsilyltungsten complexes (2.53−2.63 Å) . The W−Si(1) bond distance is slightly shorter than those of the donor-bridged bis(silylene)tungsten complexes 3 (2.49−2.51 Å),8g however, slightly longer than that in a (perchlorodisilanyl)tungsten complex (η-C 5 Me 5 )W(CO) 2 (PMe 3 )SiCl 2 SiCl 3 (2.469(2) Å) 17b. The Si(1)−O(3) distance (1.774(6) Å) is much longer than the usual Si−O single bonds (1.58−1.70 Å) and in the range of the reported Si−O(HMPA) distance of the HMPA-coordinated silyleneiron and -chromium complexes (1.67−1.78 Å) …”

“…A similar trans configuration was commonly observed in phosphine-substituted silyltungsten complexes of the type CpW(CO) 2 (PR 3 )SiR‘ 3 . The W−Si(1) bond distance is slightly shorter than those of the donor-bridged bis(silylene)tungsten complexes 3 (2.49−2.51 Å),8g however, slightly longer than that in a (perchlorodisilanyl)tungsten complex (η-C 5 Me 5 )W(CO) 2 (PMe 3 )SiCl 2 SiCl 3 (2.469(2) Å) 17b.…”

Reactions of Hydrosilanes with Transition-Metal Complexes: Formation of Stable Transition-Metal Silyl Compounds

“…Structural data reported for silyl−transition-metal complexes prepared from hydrosilanes and that include only those derivatives with “classical” M−Si, M−H, and/or Si−H bonds are summarized in Table . − …”

“…SiMo: 2.550(2); 2.556(4); 2.556(2), 2.558(2), 2.559(2); 2.670(2) . SiW: 2.388(6); 2.469(2); 2.533(3); 2.544(4); 2.547(4); 2.551(2), 2.559(4); 2.559(2); 2.565(4); 2.591(3); 2.606(2); 2.633(2); 2.652(2) …”