259173-65-4Relevant academic research and scientific papers
Alkinol- und alkindiol-funktionalisierte zirconocen-verbindungen: Synthese, struktur und reaktionsverhalten 1
Lang, Heinrich,Weinmann, Susanne,Herres, Mathias,Weinmann, Markus,Walter, Olaf,Nuber, Bernhard,Zsolnai, Laszlo
, p. 49 - 61 (1996)
The reaction of [Zr]Cl2 (1) {[Zr] = (η5-C5H4SiMe3)2Zr} with HO(CR2)nC≡CH (2a: R = H, n = 2; 2b: R = H, n = 4; 2c: R = CH3, n = 1) or HOCH2C≡CCH2OH (2d) yields, depending on the nature of the bases used [1,4-diazabicyclo[2.2.2]octane (DABCO) or NEt3], different substitution products. On treatment of 1 with 2a or 2b in toluene in the presence of DABCO, the σ-alkynol-substituted zirconocenechlorides [Zr](Cl)[O(CH2)nC≡CH] (3a: n = 2; 3b: n = 4) are formed. Moreover, zirconocene σ-dialkynols [Zr][O(CR2)nC≡CH]2 (4a: R = H, n = 2; 4b: R = H, n = 4; 4c: R = CH3, n = 1) can be obtained by treatment of compounds 1, 3a or 3b with 2a-2c in NEt3. When 2d is reacted with two equivalents of 1 in the presence of DABCO, the product isolated is (Cl)[Zr](μ,-OCH2C≡CCH2O)[Zr](Cl) (5), while in NEt3 as solvent cyclic [Zr] (μ-OCH2C≡CCH2O)2[Zr] (6) is obtained. The chemical behaviour of compounds 3 and 4 is discussed. The reaction of [Zr](Cl)[O(CH2)2C≡CH] (3a) with [CuO2CMe]4 (7) yields [Zr](Cl)(μ,-O2CMe) (8) by elimination of [CuO(CH2)2C≡CH]n. Treatment of compounds 3a, 4a or 4c with Co2(CO)8 (9) affords [Zr](Cl){[η2-O(CH2)2C≡CH] Co2(CO)6} (10), [Zr]{[η2-O(CH2)2C≡CH] Co2(CO)6}2 (11a) or [Zr]{[η2-OCMe2C≡CH]Co2(CO)6}2 (11b) respectively. In each of these compounds the HC≡C building block is η2-coordinated to a Co2(CO)6 fragment. Treatment of complexes 3a, 4b, 10 or 11 with HCl(aq) produces [Zr]Cl2 (1) and 2a or 2b [reaction of 3 or 4 with HCl(aq)] or [Zr]Cl2 (1) and [η2-HO(CH2)2C≡CH]Co2(CO)6 (12a) or (η2-HOCMe2C≡CH)Co2(CO)6 (12b) [reaction of 10 or 11 with HCl(aq)]. The solid state structures of compounds [Zr](Cl)[O(CH2)2C≡CH] (3a), (Cl)[Zr](μ-OCH2C≡CCH2O)[Zr](Cl) (5) and [Zr]{[η2-OCMe2C≡CH]Co2(CO)6}2 (11b) are reported. 3a crystallizes in the rhombic space group Pnma with cell constants a = 813.1(3), b = 1523.7(5), c = 1850.0(6) pm, V = 2292.0(9) × 106 pm3 and Z = 4. Crystals of 5 and 11b are monoclinic. Compound 5: space group Pc with a = 1290.8(6), b - 2582(1), c - 760.1(3) pm, β = 73.15(3)°, V = 2424(2) × 106 pm3 and Z = 2. Compound 11b: space group P21/n with a = 1461.0(6), b = 2057(1), c = 1528.4(6) pm, β= 96.06(3)°, V = 4567(3) × 106 pm3 and Z = 4.
