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Reaction of [Mn3(OAc)6O•3H2O]+ (1) with ferrocenyl β-diketones of the type FcCOCH2COR with R = CF3 (2a) and CH3 (2b), Ph = C6H5 (2c), and Fc = FeII(η5-C5H4)(η5-C5H5) (2d) yielded a series of ferrocene-functionalized β-diketonato manganese(III) complexes 3a-3d, respectively, of general formula [Mn(FcCOCHCOR)3]. The mixed-ligand β-diketonato complex [Mn(FcCOCHCOFc)2(FcCOCHCOCH3)] (4) was obtained by reacting mixtures of diketones 2b and 2d with 1. A single-crystal X-ray structure determination of 3b (Z = 2, triclinic, space group P1̅) highlighted a weak axial elongating Jahn-Teller effect and a high degree of bond conjugation. An X-ray photoelectron spectroscopic study, by virtue of linear relationships between group electronegativities of ligand R groups, χR, or ∑χR, and binding energies of both the Fe 2p3/2 and Mn 2p3/2 photoelectron lines, confirmed communication between molecular fragments of 2a-2d as well as 3a-3d. This unprecedented observation allows prediction of binding energies from known β-diketonato side group χR values. [ABSTRACT FROM AUTHOR]

The bimetallic paddlewheel catalyst precursor, [PdIICoII(μ-OOCCH3)4] H2O·2CH3COOH (1), prepared from[Pd3(μ-OOCCH3)6] and [Co(OOCCH3)2], was used as a single source precursor to prepare,after binding to a surface-hydroxylated silicon wafer and oxidation,the bimetallic oxides of PdIVCoIII/SiO2catalyst supported on a model planar (i.e., two-dimensional) siliconwafer. This catalyst catalyzes the aerobic oxidation of alcohols toits corresponding carbonyl compounds. The bimetallic tetracarboxylatocatalyst precursor was bonded to the surface-hydroxylated siliconwafer by spin-coating and also by grafting. X-ray photoelectron spectroscopy(XPS) revealed that one of the four μ-acetato bridging ligandswas substituted by Si–O fragments in a covalent bond formationprocess during grafting of 1onto the wafer. In contrast,during the spin-coating process, all four acetato ligands remainedintact during fixation on the silicon surface. Upon oxidation andworkup, the grafted sample’s Pd:Co ratio remained unchanged(1.0:1.3), whereas the spin-coated sample’s Pd content decreasedwith respect to Co content. XPS determined binding energies were interpretedto imply that after oxidation in an oxygen/argon mixture of the graftedsample both PdIIand CoIIwere oxidized to producePdO2(337.5 eV) and CoIII2O3(781.1 eV) which most probably interacts with the silicon surfacevia PdIV–O–Si and CoIII–O–Sibonds. Solvent free aerobic oxidation of octadecanol to its correspondingcarbonyl compound was achieved on this oxidized PdIVCoIII/SiO2model catalyst using molecular oxygen asoxidant under solvent-free conditions. The use of the single sourcecatalyst precursor, 1, resulted in a PdIVCoIII/SiO2catalyst with superior catalytic activitytoward the oxidation of octadecanol over a catalyst prepared froma physical mixture of the separate reactant compounds tripalladium(II)hexaacetate and cobalt(II) diacetate. [ABSTRACT FROM AUTHOR]

Treatment of hydroxylated silica nanopowders S1 and allyl-functionalized silica nanopowders S2 with 3-(diphenylborano)- or 3-bis(pentafluorophenylborano)propyltrimethoxysilane or 2-(diphenylphosphino)- or 2-(dicyclohexylphosphino)ethyltriethoxysilane generates silica nanopowder supported Lewis acids S3 and silica nanopowder supported Lewis bases S4 . These surfaces were characterized by 13 C, 11 B, and 31 P cross-polarization magic angle spinning nuclear magnetic resonance (CP MAS NMR), X-ray photoelectron spectroscopy (XPS), and attenuated total reflection Fourier transform infrared (ATR FTIR). When S3 is combined with solution-phase Lewis bases PR 3 (R = C 6 F 5 , C 6 H 5 , mesityl), six associated silica nanopowder supported frustrated Lewis pairs (FLPs) are formed. In another set of six reactions, the interactions between the supported Lewis bases S4 and solution-phase Lewis acids BR 3 with R = C 6 F 5 , C 6 H 5 , mesityl produced six more associated supported FLPs. The capture of CO 2 by these FLPs producing FLP-CO 2 Lewis pair adducts S5 and S6 were highlighted by ATR FTIR, and it was found that FLP S5e with R = C 6 H 5 on both the supported Lewis acid and solution-phase Lewis base trapped the largest quantities of CO 2 on the silica nanopowder supports. Conversion of CO 2 to HCOOH was achieved by first activating H 2 to generate activated FLP-H 2 surfaces S7 and S9 . Addition of CO 2 then generated HCOOH via the silica nanopowder supported FLP-HCOOH adducts S8 and S10 . Qualitative identification of HCOOH generation was achieved by ATR FTIR measurements, and surface 10b with R = C 6 H 5 proved to be the most successful silica nanopowder surface bound FLP in HCOOH generation. In some cases, diborano formates (-BO(CH)OB-) S11 and S12 were also identified as side products during HCOOH formation. Spectroscopic characterization of purposefully synthesized S11 and S12 included 11 B and 31 P CP MAS NMR.

Reaction of [Mn3(OAc)6O·3H2O](+) (1) with ferrocenyl β-diketones of the type FcCOCH2COR with R = CF3 (2a) and CH3 (2b), Ph = C6H5 (2c), and Fc = Fe(II)(η(5)-C5H4)(η(5)-C5H5) (2d) yielded a series of ferrocene-functionalized β-diketonato manganese(III) complexes 3a-3d, respectively, of general formula [Mn(FcCOCHCOR)3]. The mixed-ligand β-diketonato complex [Mn(FcCOCHCOFc)2(FcCOCHCOCH3)] (4) was obtained by reacting mixtures of diketones 2b and 2d with 1. A single-crystal X-ray structure determination of 3b (Z = 2, triclinic, space group P1̅) highlighted a weak axial elongating Jahn-Teller effect and a high degree of bond conjugation. An X-ray photoelectron spectroscopic study, by virtue of linear relationships between group electronegativities of ligand R groups, χR, or ∑χR, and binding energies of both the Fe 2p3/2 and Mn 2p3/2 photoelectron lines, confirmed communication between molecular fragments of 2a-2d as well as 3a-3d. This unprecedented observation allows prediction of binding energies from known β-diketonato side group χR values.