Katrin Köhler

Unusual coordination mode of organogold(I) compounds: trigonal-planar complexation of gold (I) centers by alkynes

Linearily directed donor-stabilized organogold (I) compounds react with the 3-titanopenta-1,4-diyne [(η5-C5H4SiMe3)2 Ti(CCsiMe3)2]T 1 to afford complexes 1·Au(η1-R)[R = Me 3a, C6H2(CF3)3-2,4,6 3b, CCSiMe3 3c] in which the gold (I) centre possesses a trigonal-planar environment formed by two η2-coordinated alkyne units and a η1-bonded organic group R; the X-ray structure analysis of [{(η5-C5H4SiMe3)2 Ti(CCSiMe3)2}-Au{η1-C6H2(CF3)2-2,4,6}] 3b is reported.

Monomere alkin-stabilisierte kupfer(I)-halogenid-und kupfer(I)-pseudohalogenid-verbindungen; kristallstruktur von [(η5-C5H4SiMe3)2Ti(CCPh)2]CuCl

The reaction of Me3SiCCSiMe3 (bd1}), LnMCSiMe3 (4a, LnMCp(CO)2Fe; 4b, LnMCp(CO)3Mo] and E(CCR)2 (6, EMe2Si; 8, E(η5-C5H4SiMe3)2Ti; R is a singly bonded organic ligand) with CuX (2) (X is a halide or pseudohalide) is described. 1 and 4 react CuX (2a, XCl; 2b, XBr; 2c, XI; 2d, XOSO2CF3) to yield the dimeric compounds [(η2-Me3SiCCSiMe3)CuX]2 (3a, XCl 3b, XBr; 3c, XI; 3d, XOSO2CF3) or [(η2-LnMCCSiMe3)CuX]2 (5a, LnMCp(CO)2Fe, XCl; 5b, LnMCp(CO)3Mo, XCl) respectively. In these compounds the C2 building block is η2-coordinated to a CuX moiety and by the formation of copper-X-bridges (Cu2X2) a dimer is formed. However, the reaction of Me2Si(CCSiMe3) (CCR) (6a, RSiMe3; 6b, RH) with CuX (2) (XCl, Br, OSO2CF3, O2CMe) affords polymeric Me2Si[η2-CCSiMe3})(η2-CCRCu2X2]n (7a RSiMe3, XCl; 7b, RSiMe3, XBr; 7c, RH, XCl; 7d, RH, XBr; 7e, RSiMe3, XOSO2CF3; 7f, RSiMe3, XO2CMe) in high yields. In 7a–7f each alkynyl fragment is η2-coordinated to a CuX unit. While the reaction of 6a or 6b with CuX yields polymeric 7a–7f, the organometallic 1,4-diyne RCC-[Ti]-CCR ([Ti](η5-C5H4SiMe3)2Ti; 8a, RPh; 8b, RSiMe3) affords with CuX (2a, XCl; 2b, XBr; 2c, XI; 2e, XCN; 2f, XSCN) the dinuclear compounds [(η5-C5H4SiMe3)2Ti(CCR)2]CuX (9a, RPh, XCl; 9b RSiMe3, XCl; 9c, RSiMe3, XBr; 9d, RSiMe3, XI; 9e, RSiMe3, XCN; 9f, RSiMe3, XSCN). Compounds 9a–9f feature a monomeric copper(I) halide or copper(I) pseudohalide moiety, which is stabilized by the chelating effect of the alkynyl ligands in [Ti](CCR)2. [(η5-C5H4SiMe3)2Ti(CCSiMe3)2]CuCl (9b) reacts with AgX (XCN, SCN, O2CMe, O2CPh) to yield [(η5-C5H4SiMe3)2Ti(CCSiMe3)2CuX (9e, XCN; 9f, XSCN; 9g, XOC(O)Me; 9h, XOC(O)Ph) by precipitation of AgCl. In addition, the bis(alkynyl)-ansa-titanocene [(η5-C5H4)Me2Si(η5-C5H3SiMe3)]Ti(CCSiMe3)2 (10) yields with CuCl (2a) the dinuclear species {[η5-C5H4)Me2Si(η5-C5H3SiMe3})]Ti(CCSiMe3)2CuCl (11). The identity of compounds 3, 5, 7, 9 and 11 is confirmed by analytical and spectroscopic (IR, MS, 1H, 13C NMR) data, and that of [(η5-C5H4SiMe3)2Ti(CCPh)2]CuCl (9a) is confirmed by X-ray analysis. Crystals of 9a are monoclinic, space group Pc with cell constant a = 992.6(7), b = 1210(1), c = 1335.5(7) pm, β = 105.75(5)°, V = 1543(2) × 106 pm3 and Z = 2.

Alkinol- und Alkindiol-substituierte Titanocen-Komplexe; Synthese, Reaktionsverhalten und Strukturmerkmale / Alkyne-ol and Alkyne-diol Substituted Titanocene Complexes; Synthesis, Reaction Behaviour and Structural Features

The reaction of (η5-C5H4SiMe3)2TiCl2 (1) with HO(CH2)nC ≡ CR (2a: n = 1, R = H; 2b: n = 1, R = CH3; 2c: n = 1, R = CH2OH ; 3: n = 2, R = H; 4: n = 4, R = H) affords in toluene at 25 °C in the presence of NEt3 the monoalkyne-ol substituted titanocenes (η5-C5H4SiMe3)2Ti(Cl)[O(CH2)nC ≡ CR] (5a: n = 1. R = H; 5b: n = 1, R = CH3; 5c: n = 1, R = C H2OH; 6: n = 2, R = H; 7: n = 4. R = H ). Compound 5c reacts with one equivalent of 1 in the presence of NEt3 to yield (η5-C5H4SiMe3)2(Cl)Ti-OCH2C ≡ CCH2O -Ti(Cl)(η5-C5H4SiMe3)2 (8). In addition, compound 8 can be synthesized directly by treatment of (η5- C5H4SiMe3)2TiCl2 (1) with 0.5 equivalents of HOCH9C≡CCH2OH (2c) in the presence of NEt3. The reaction of (η5-C5H4SiMe3)2Ti(Cl)(OCH2C ≡ CCH3) (5b) with Co2(CO)8 (9) yields (η5-C5H4SiMe3)2Ti(Cl)[(η2-OCH2C ≡ CCH3)Co2(CO)6] (10). Treatment of 5b or 10 with HCl(aq) (11) leads to the formation of (η5-C5H4SiMe3)2TiCl2 (1) and HOCH2C ≡ CCH3 (2b) (reaction of 5b with 11) or (η5-C5H4SiMe3)2TiCl2 (1) and [(η2-HOCH2C ≡ CCH3)Co2(CO)6] (12) (reaction of 10 with 11). All compounds have been characterized by analytical and spectroscopic data (IR , 1H, 13C NMR, MS) and (η5-C5H4SiMe3)2Ti(Cl)(OCH2C ≡ CCH3) (5b) by X -ray analysis.