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The trivalent metal cations Al(3+) , Cr(3+) , and Fe(3+) were each introduced, together with Sc(3+) , into MIL-100(Sc,M) solid solutions (M=Al, Cr, Fe) by direct synthesis. The substitution has been confirmed by powder X-ray diffraction (PXRD) and solid-state NMR, UV/Vis, and X-ray absorption (XAS) spectroscopy. Mixed Sc/Fe MIL-100 samples were prepared in which part of the Fe is present as α-Fe2 O3 nanoparticles within the mesoporous cages of the MOF, as shown by XAS, TGA, and PXRD. The catalytic activity of the mixed-metal catalysts in Lewis acid catalysed Friedel-Crafts additions increases with the amount of Sc present, with the attenuating effect of the second metal decreasing in the order Al>Fe>Cr. Mixed-metal Sc,Fe materials give acceptable activity: 40 % Fe incorporation only results in a 20 % decrease in activity over the same reaction time and pure product can still be obtained and filtered off after extended reaction times. Supported α-Fe2 O3 nanoparticles were also active Lewis acid species, although less active than Sc(3+) in trimer sites. The incorporation of Fe(3+) into MIL-100(Sc) imparts activity for oxidation catalysis and tandem catalytic processes (Lewis acid+oxidation) that make use of both catalytically active framework Sc(3+) and Fe(3+) . A procedure for using these mixed-metal heterogeneous catalysts has been developed for making ketones from (hetero)aromatics and a hemiacetal.

A cobalt-catalysed C–H carbonylation of aliphatic carboxamide derivatives is described, employing commercially available Co(ii)-salts in the presence of a silver oxidant.

The isothiourea-catalysed enantioselective synthesis of cis-pyrrolizines is explored synthetically and computationally.

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The ether which had been removed by distillation was found to contain acetone, identified by conversion to dibenzalacetone, m. p. 111.5-112.5°, both alone and when mixed with an authentic sample.Oxidation of Saturated Ketones to Acids: (1) Methyl re-Amyl Ketone Condensation.-Five-hundredths mole of 2-methyl-5-decanone was oxidized with 0.15 mole of sodium dichromate, 0.6 mole of sulfuric acid and 250 ml. of water as previously described.2a•16 Considerable carbon dioxide was evolved at the start and throughout the course of the oxidation. A total of 0.09 mole of acid was obtained. re-Caproic acid was identified in the waterinsoluble acid fraction by conversion to the 2-alkyl benzimidazole,17 m. p. 157-158°, which showed no depression when mixed with the known re-caproic acid derivative, m. p. 158-158.5°. Acetic acid was shown to be present in the water-soluble fraction by preparing the £-toluide, m. p. 146.5-147.5°, alone and when mixed with known acetop-toluide.(2) Methyl re-Hexyl Ketone Condensation.-Five-hundredths mole of 2-methyl-5-undecanone, oxidized as above, gave 1.1 moles of total acids. re-Heptoic acid was identified in the water-insoluble fraction by conversion to the piperazonium salt,18 m. p. 97-98°, which showed no depression when mixed with authentic piperazonium di-ro-heptoate, m. p. 96-97 °. Isovaleric acid was also shown to be present by preparing the piperazonium salt, m. p. 140-141°, alone

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