Coniuga et impera: A bifunctional solid catalyst is prepared by combining acid and base functions on mesoporous silica supports (see picture). The co‐existence of these functions is shown by a two‐step reaction sequence in one pot. Excellent product yields, which cannot be obtained by separated acid and base functions in one pot, show the validity of our concept.

Copper on γ-alumina and on mixed magnesia-alumina, Cu/MgO-Al 2 O 3 , catalyse the hydrodeoxygenation (HDO) of β-O-4 lignin-type dimers, giving valuable aromatics. The typical selectivity to phenol is as high as 20%. By changing the support's acidity we can modify the dispersion of copper. Interestingly, more HDO occurs with larger copper agglomerates than with finely dispersed particles. The presence of copper also increases the selectivity of the HDO cleavage. Three different pathways are hypothesized for the reaction on the catalyst surface. Thus, copper activates ketones more and especially more selective towards cleavage than their corresponding alcohols. DFT calculations of bond dissociation energies correlate well with this experimental observation. Excitingly, ethylbenzene is formed in proportional amounts to phenol, showing that these catalysts can reduce the oxygen content of lignin-type product streams. Considering its low price and ready availability, we conclude that copper on alumina is a promising alternative catalyst for lignin depolymerization. † Electronic supplementary information (ESI) available: 1 H NMR spectra of 1 and 2, and surface area measurements (BET) of both catalysts. See

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Triethynyl methanol, a key intermediate in the synthesis of carbon nets, and some derivatives have been synthesized by oxidation of the corresponding secondary alcohol and reaction with lithio(trimethylsilyI)acetylene.

A number of new N-heterocyclic carbene (NHC) ligands were synthesized via a multicomponent reaction, wherein an aldehyde or ketone, a primary amine and an α-acidic isocyanide were reacted, giving the corresponding 2H-2-imidazolines. These were easily alkylated with an alkyl halide at position N-3, yielding the final NHC precursors, that were then complexed with Ru in situ. The resulting complexes are shown to be active and selective catalysts for the transfer hydrogenation of furfural to furfurol, using isopropanol as the hydrogen source. Importantly, the carbene ligand remains coordinated to the ruthenium center throughout the reaction.

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