Hydrogenation of Carbon Dioxide and Aryl Isocyanates by a Tetranuclear Tetrahydrido Yttrium Complex. Isolation, Structures, and CO₂ Insertion Reactions of Methylene Diolate and μ₃-Oxo Yttrium Complexes

The reaction of carbon dioxide with a tetranuclear tetrahydrido yttrium complex [(C5Me4SiMe3)Y(μ-H)]4(L) (L = Me3SiCC(H)C(H)CSiMe3) (1) rapidly afforded the corresponding bis(methylene diolate) complex [(C5Me4SiMe3)Y]4(μ-O2CH2)2(L) (2), while the reactions of an aryl isocyanate with 1 led to selective formation of the μ3-oxo complex [(C5Me4SiMe3)Y]4(μ-O)( μ-H)2(L) (5) or [(C5Me4SiMe3)Y]4(μ-O)2(L) (7), depending on the substrate ratio. Both the methylene diolate and the oxo complexes can undergo CO2 insertion reactions to give the corresponding carbonate complexes. These reactions not only yield a new series of polynuclear yttrium complexes having novel structures but also shed new light on the mechanistic aspects of the heterogeneous hydrogenation of CΟ2. The high reactivity of the polynuclear μ3-oxo yttrium complexes 5 and 7 could also make them novel molecular models for study of metal oxide-supported catalysts

Tetranuclear Rare Earth Metal Polyhydrido Complexes Composed of “(C₅Me₄SiMe₃)LnH₂” Units. Unique Reactivities toward Unsaturated C−C, C−N, and C−O Bonds

The tetranuclear Lu and Y polyhydrido complexes [(C5Me4SiMe3)Ln(μ-H)2]4(THF) (Ln = Lu, Y) undergo novel multiple hydrogenation reactions with unsaturated organic compounds such as benzonitrile, γ-butyrolactone, styrene, and 1,4-bis(trimethylsilyl)-1,3-butadiyne to afford a series of structurally characterizable polynuclear complexes that possess novel structures and are otherwise difficult to access. Most of these reactions are unprecedented and can be attributed to the unique cooperative effects of multiple active sites in the polyhydrido rare earth metal complexes

Tetranuclear Rare Earth Metal Polyhydrido Complexes Composed of “(C₅Me₄SiMe₃)LnH₂” Units. Unique Reactivities toward Unsaturated C−C, C−N, and C−O Bonds

The tetranuclear Lu and Y polyhydrido complexes [(C5Me4SiMe3)Ln(μ-H)2]4(THF) (Ln = Lu, Y) undergo novel multiple hydrogenation reactions with unsaturated organic compounds such as benzonitrile, γ-butyrolactone, styrene, and 1,4-bis(trimethylsilyl)-1,3-butadiyne to afford a series of structurally characterizable polynuclear complexes that possess novel structures and are otherwise difficult to access. Most of these reactions are unprecedented and can be attributed to the unique cooperative effects of multiple active sites in the polyhydrido rare earth metal complexes

Hydrogenation of Carbon Dioxide and Aryl Isocyanates by a Tetranuclear Tetrahydrido Yttrium Complex. Isolation, Structures, and CO₂ Insertion Reactions of Methylene Diolate and μ₃-Oxo Yttrium Complexes

The reaction of carbon dioxide with a tetranuclear tetrahydrido yttrium complex [(C5Me4SiMe3)Y(μ-H)]4(L) (L = Me3SiCC(H)C(H)CSiMe3) (1) rapidly afforded the corresponding bis(methylene diolate) complex [(C5Me4SiMe3)Y]4(μ-O2CH2)2(L) (2), while the reactions of an aryl isocyanate with 1 led to selective formation of the μ3-oxo complex [(C5Me4SiMe3)Y]4(μ-O)( μ-H)2(L) (5) or [(C5Me4SiMe3)Y]4(μ-O)2(L) (7), depending on the substrate ratio. Both the methylene diolate and the oxo complexes can undergo CO2 insertion reactions to give the corresponding carbonate complexes. These reactions not only yield a new series of polynuclear yttrium complexes having novel structures but also shed new light on the mechanistic aspects of the heterogeneous hydrogenation of CΟ2. The high reactivity of the polynuclear μ3-oxo yttrium complexes 5 and 7 could also make them novel molecular models for study of metal oxide-supported catalysts

Tetranuclear Rare Earth Metal Polyhydrido Complexes Composed of “(C₅Me₄SiMe₃)LnH₂” Units. Unique Reactivities toward Unsaturated C−C, C−N, and C−O Bonds

The tetranuclear Lu and Y polyhydrido complexes [(C5Me4SiMe3)Ln(μ-H)2]4(THF) (Ln = Lu, Y) undergo novel multiple hydrogenation reactions with unsaturated organic compounds such as benzonitrile, γ-butyrolactone, styrene, and 1,4-bis(trimethylsilyl)-1,3-butadiyne to afford a series of structurally characterizable polynuclear complexes that possess novel structures and are otherwise difficult to access. Most of these reactions are unprecedented and can be attributed to the unique cooperative effects of multiple active sites in the polyhydrido rare earth metal complexes

Isolation and Structural Characterization of a Polyhydrido Lanthanide Cluster Complex Consisting of “(C₅Me₄SiMe₃)LuH₂” Units

Reaction of the mixed alkyl/hydride complex [Cp‘Lu(CH2SiMe3)(μ-H)(THF)]2 (2; Cp‘ = C3Me4SiMe3) with 1 equiv of PhSiH3 (per Lu) in benzene or OEt2 afforded the polyhydrido cluster [Cp‘LuH2]4 (3), while hydrogenolysis of 2 with H2 (1 atm) in THF yielded the THF-coordinated complex [Cp‘Lu(μ-H)2]4(THF) (4). Complexes 3 and 4 are interconvertible, without decomposition or ligand redistribution

Tetranuclear Rare Earth Metal Polyhydrido Complexes Composed of “(C₅Me₄SiMe₃)LnH₂” Units. Unique Reactivities toward Unsaturated C−C, C−N, and C−O Bonds

The tetranuclear Lu and Y polyhydrido complexes [(C5Me4SiMe3)Ln(μ-H)2]4(THF) (Ln = Lu, Y) undergo novel multiple hydrogenation reactions with unsaturated organic compounds such as benzonitrile, γ-butyrolactone, styrene, and 1,4-bis(trimethylsilyl)-1,3-butadiyne to afford a series of structurally characterizable polynuclear complexes that possess novel structures and are otherwise difficult to access. Most of these reactions are unprecedented and can be attributed to the unique cooperative effects of multiple active sites in the polyhydrido rare earth metal complexes

Hydrogenation of Carbon Dioxide and Aryl Isocyanates by a Tetranuclear Tetrahydrido Yttrium Complex. Isolation, Structures, and CO₂ Insertion Reactions of Methylene Diolate and μ₃-Oxo Yttrium Complexes

The reaction of carbon dioxide with a tetranuclear tetrahydrido yttrium complex [(C5Me4SiMe3)Y(μ-H)]4(L) (L = Me3SiCC(H)C(H)CSiMe3) (1) rapidly afforded the corresponding bis(methylene diolate) complex [(C5Me4SiMe3)Y]4(μ-O2CH2)2(L) (2), while the reactions of an aryl isocyanate with 1 led to selective formation of the μ3-oxo complex [(C5Me4SiMe3)Y]4(μ-O)( μ-H)2(L) (5) or [(C5Me4SiMe3)Y]4(μ-O)2(L) (7), depending on the substrate ratio. Both the methylene diolate and the oxo complexes can undergo CO2 insertion reactions to give the corresponding carbonate complexes. These reactions not only yield a new series of polynuclear yttrium complexes having novel structures but also shed new light on the mechanistic aspects of the heterogeneous hydrogenation of CΟ2. The high reactivity of the polynuclear μ3-oxo yttrium complexes 5 and 7 could also make them novel molecular models for study of metal oxide-supported catalysts

Hydrogenation of Carbon Dioxide and Aryl Isocyanates by a Tetranuclear Tetrahydrido Yttrium Complex. Isolation, Structures, and CO₂ Insertion Reactions of Methylene Diolate and μ₃-Oxo Yttrium Complexes

The reaction of carbon dioxide with a tetranuclear tetrahydrido yttrium complex [(C5Me4SiMe3)Y(μ-H)]4(L) (L = Me3SiCC(H)C(H)CSiMe3) (1) rapidly afforded the corresponding bis(methylene diolate) complex [(C5Me4SiMe3)Y]4(μ-O2CH2)2(L) (2), while the reactions of an aryl isocyanate with 1 led to selective formation of the μ3-oxo complex [(C5Me4SiMe3)Y]4(μ-O)( μ-H)2(L) (5) or [(C5Me4SiMe3)Y]4(μ-O)2(L) (7), depending on the substrate ratio. Both the methylene diolate and the oxo complexes can undergo CO2 insertion reactions to give the corresponding carbonate complexes. These reactions not only yield a new series of polynuclear yttrium complexes having novel structures but also shed new light on the mechanistic aspects of the heterogeneous hydrogenation of CΟ2. The high reactivity of the polynuclear μ3-oxo yttrium complexes 5 and 7 could also make them novel molecular models for study of metal oxide-supported catalysts

Tetranuclear Rare Earth Metal Polyhydrido Complexes Composed of “(C₅Me₄SiMe₃)LnH₂” Units. Unique Reactivities toward Unsaturated C−C, C−N, and C−O Bonds

The tetranuclear Lu and Y polyhydrido complexes [(C5Me4SiMe3)Ln(μ-H)2]4(THF) (Ln = Lu, Y) undergo novel multiple hydrogenation reactions with unsaturated organic compounds such as benzonitrile, γ-butyrolactone, styrene, and 1,4-bis(trimethylsilyl)-1,3-butadiyne to afford a series of structurally characterizable polynuclear complexes that possess novel structures and are otherwise difficult to access. Most of these reactions are unprecedented and can be attributed to the unique cooperative effects of multiple active sites in the polyhydrido rare earth metal complexes