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Abstract  The reaction of Ru3(CO)12 with 2(diphenylphosphino)ethyl-triethoxysilane (DPTS) in hydrocarbons, leads to the functionalized Ru3(CO)12−n [Ph2P(CH2)2Si(OEt3)] n (n = 1,2) complexes. The complex with two phosphine substituents was chemically anchored on mesoporous silicas, SBA-15 and MCM-41, in order to obtain two hybrid materials characterized by a different localization of the metal centre on the surface of the porous supports. A detailed investigation of the cluster, before and after chemical anchoring on the mesoporous silicas, was pursued. Particular attention was also devoted to the study of the morphological, structural and textural properties of the metal-functionalised silicas (Ru/SBA-15 and Ru/MCM-41) by infrared spectroscopy (FT-IR), scanning electron microscopy, X-ray diffraction and N2 physisorption analysis. [ABSTRACT FROM AUTHOR]

Abstract  The thermal reactions of 2-methyl-1-hexen-3-yne [CH3CH2C≡CC(=CH2)CH3, metey] with Fe3(CO)12 have been studied: cluster opening or fragmentation and alkyne dimerization occur. Main products are the open triangular isomers [Fe3(CO)6(μ-CO)2{CH3(=CH2)CC(Et)C(Et)C(=CH2)CH3}] (complex 3a) and [Fe3(CO)6(μ-CO)2{C(Et)CCH3(=CH2)C(Et)CCH3(=CH2)}] (complex 3b). The structure and isomerism of the complexes has been confirmed by X-ray studies. The minor products of the reaction have been characterized by spectroscopic techniques. An attempt at exploiting the reactivity of the “free” C=C bonds of the coordinated ene-yne was made: complex 3a was reacted with styrene under thermal conditions. Unexpectedly considerable yields of the closed triangular cluster [Fe3(CO)6{EtC2C(=CH2)CH3}2] (complex 5) have been obtained. This behaviour had not been previously observed. The unprecedented structure of complex 5 has been confirmed with an X-ray study. [ABSTRACT FROM AUTHOR]

Abstract  The title complex is the main product of the reaction of Fe3(CO)12 with isopropenylacetylene in basic methanolic solution (followed by acidification); it is obtained upon carbon–carbon bond forming and dimerization of the alkyne. The same complex is also obtained by reacting Fe3(CO)12 in CH3OH/KOH solution with 2-methyl-hex-1-en-3-yne; carbon–carbon bond cleavage presumably occurs to form isopropenylacetylene, which then reacts with the iron carbonyl. The unprecedented structure of the complex has been determined with a X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

The new alkoxysilyl-functionalized alkynes [HC≡CCH2N(H)C(=O)N(H)(CH2)3Si(OEt)3] and [HC≡C(C6H4)–N(H)C(=O)N(H)(CH2)3Si(OEt)3] have been synthesized using literature methods. These have been reacted with Fe3(CO)12, Ru3(CO)12 and Co2(CO)8. With the iron carbonyl only decomposition was observed: with Ru3(CO)12 splitting of the alkynes into their parent components and formation of the complexes (μ-H)Ru3(CO)9[HC=N(CH2)3Si(OEt)3], (μ-H)Ru3(CO)9[C–C(C6H4)NH2] and (μ-H)2Ru3(CO)9[HC–CCH3] occurred. Finally, with Co2(CO)8 formation of complexes Co2(CO)6(HC2R) R=(C6H4)NH2, CH2NH(CO)NH(CH2)3Si(OEt)3, (C6H4)NH(CO)NH(CH2)3Si(OEt)3 containing the intact alkynes could be obtained. [ABSTRACT FROM AUTHOR]

Abstract  Ru3(CO)12 has been reacted with the compounds hex-1-en-3-yne [EtC≡CCH=CH2], 2-methyl-hex-1-en-3-yne [EtC≡CC(=CH2)CH3] and with 3(ethoxy-silyl)propyl isocyanate [(EtO)3Si(CH2)3NCO] and the compound tb [(EtO)3Si(CH2)3NHC(=O)OCH2C≡CCH2OC(=O)NH(CH2)3Si(OEt)3] in hydrocarbon solution. Some reactions in CH3OH/KOH solution (followed by acidification) have also been performed. The main products of the reactions with ene-ynes are the clusters Ru3(CO)6(μ-CO)2L2 (L = C6H8, C7H10) and their demolition products, the “ferrole” Ru2(CO)6L2 complexes. One of the isomers of Ru3(CO)6(μ-CO)2L2, and Ru2(CO)6L2 (L = C7H10) have been reacted with vinyl-triethoxysilane [(EtO)3SiCH=CH2]: these reactions did not afford complexes containing new carbon–carbon bonds or triethoxy-silyl groups. Only polymerization of vinyl-triethoxysilane occurred. The reactions of Ru3(CO)12 with triethoxysilyl-propyl-isocyanate and tb (in the presence of Me3NO) lead to the same products, that is the isomeric complexes (μ-H)Ru3(CO)9[C=N(H)(CH2)3Si(OEt)3] with a “perpendicular” ligand (complex 3, as proposed on the basis of spectroscopic results) and (μ-H)Ru3(CO)9[HC=N(CH2)3Si(OEt)3] with a “parallel” ligand (complex 4, as confirmed by a X-ray analysis). The reaction pathways leading to these products are discussed. Complex 4 has been reacted with tetraethyl orthosilicate and the resulting material has been characterized. These reactions are part of a study on the synthesis of inorganic-organometallic materials through sol–gel techniques. [ABSTRACT FROM AUTHOR]

Co2(CO)8 has been reacted with but-2-yn-1,4-diol (BUD) and the reactivity of the resulting complex Co2(CO)6(HOCH2C≡CCH2OH) (complex 1) is discussed. Complex 1 has been reacted with all the components used in the synthesis of sol-gel materials based on tetraethyl-orthosilicate (TEOS) with the aim at obtaining evidences for the processes occurring during the formation of inorganic-organometallic sol-gel materials containing BUD. Reaction pathways are discussed. [ABSTRACT FROM AUTHOR]

Abstract  The thermal reactions of 2-methyl-1-hexen-3-yne [CH3CH2C≡CC(=CH2)CH3, metey] with Fe3(CO)12 have been studied: cluster opening or fragmentation and alkyne dimerization occur. Main products are the open triangular isomers [Fe3(CO)6(μ-CO)2{CH3(=CH2)CC(Et)C(Et)C(=CH2)CH3}] (complex 3a) and [Fe3(CO)6(μ-CO)2{C(Et)CCH3(=CH2)C(Et)CCH3(=CH2)}] (complex 3b). The structure and isomerism of the complexes has been confirmed by X-ray studies. The minor products of the reaction have been characterized by spectroscopic techniques. An attempt at exploiting the reactivity of the “free” C=C bonds of the coordinated ene-yne was made: complex 3a was reacted with styrene under thermal conditions. Unexpectedly considerable yields of the closed triangular cluster [Fe3(CO)6{EtC2C(=CH2)CH3}2] (complex 5) have been obtained. This behaviour had not been previously observed. The unprecedented structure of complex 5 has been confirmed with an X-ray study. [ABSTRACT FROM AUTHOR]

Abstract  The title complex is the main product of the reaction of Fe3(CO)12 with isopropenylacetylene in basic methanolic solution (followed by acidification); it is obtained upon carbon–carbon bond forming and dimerization of the alkyne. The same complex is also obtained by reacting Fe3(CO)12 in CH3OH/KOH solution with 2-methyl-hex-1-en-3-yne; carbon–carbon bond cleavage presumably occurs to form isopropenylacetylene, which then reacts with the iron carbonyl. The unprecedented structure of the complex has been determined with a X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Abstract  Ru3(CO)12 has been reacted with the compounds hex-1-en-3-yne [EtC≡CCH=CH2], 2-methyl-hex-1-en-3-yne [EtC≡CC(=CH2)CH3] and with 3(ethoxy-silyl)propyl isocyanate [(EtO)3Si(CH2)3NCO] and the compound tb [(EtO)3Si(CH2)3NHC(=O)OCH2C≡CCH2OC(=O)NH(CH2)3Si(OEt)3] in hydrocarbon solution. Some reactions in CH3OH/KOH solution (followed by acidification) have also been performed. The main products of the reactions with ene-ynes are the clusters Ru3(CO)6(μ-CO)2L2 (L = C6H8, C7H10) and their demolition products, the “ferrole” Ru2(CO)6L2 complexes. One of the isomers of Ru3(CO)6(μ-CO)2L2, and Ru2(CO)6L2 (L = C7H10) have been reacted with vinyl-triethoxysilane [(EtO)3SiCH=CH2]: these reactions did not afford complexes containing new carbon–carbon bonds or triethoxy-silyl groups. Only polymerization of vinyl-triethoxysilane occurred. The reactions of Ru3(CO)12 with triethoxysilyl-propyl-isocyanate and tb (in the presence of Me3NO) lead to the same products, that is the isomeric complexes (μ-H)Ru3(CO)9[C=N(H)(CH2)3Si(OEt)3] with a “perpendicular” ligand (complex 3, as proposed on the basis of spectroscopic results) and (μ-H)Ru3(CO)9[HC=N(CH2)3Si(OEt)3] with a “parallel” ligand (complex 4, as confirmed by a X-ray analysis). The reaction pathways leading to these products are discussed. Complex 4 has been reacted with tetraethyl orthosilicate and the resulting material has been characterized. These reactions are part of a study on the synthesis of inorganic-organometallic materials through sol–gel techniques. [ABSTRACT FROM AUTHOR]