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The recyclable palladium catalysts were used for selective mono- or double carbonylation under solvent-free conditions and in DMF, respectively.

Silica modified with organic dicationic moieties proved to be an excellent support for palladium catalysts used in the aminocarbonylation of aryl iodides. By an appropriate choice of the reaction conditions, the same catalyst could be used for selective mono-or double carbonylations leading to amide and aketoamide products, respectively. The best catalyst could be recycled for at least 10 consecutive runs with a loss of palladium below the detection limit. By the application of the new support, efficient catalyst recycling could be achieved under mild reaction conditions (under low pressure and in a short reaction time). Palladium-leaching data support a mechanism with dissolution-re-precipitation of the active palladium species. † Electronic supplementary information (ESI) available: Preparation of the catalysts, general procedure for aminocarbonylation reactions, 29 Si CP MAS NMR spectrum of 3, TEM images and XPS spectra of catalysts, data of recycling experiments with CAT-1 and CAT-2, characterisation of products, and 1 H and 13 C-NMR spectra of isolated products, references. See

Switchable polarity recyclable solvent mixtures were applied as reaction medium and catalyst to replace the conventional base catalysts in the Claisen–Schmidt condensation of 17‐oxo steroids with aromatic aldehydes. Reversibility between ionic and nonionic forms of the new 2‐n‐butyl‐1,1,3,3‐tetramethylguanidine (nBu‐TMG)/ethylene glycol/CO2 and 2‐tert‐butyl‐1,1,3,3‐tetramethylguanidine (tBu‐TMG)/ethylene glycol/CO2 systems were proved by conductivity measurements. The structure of the ionic form was established by 1H NMR and IR measurements and by quantum chemical calculations. The steroidal products with androstane and estrane skeleton were characterised with spectroscopic methods (NMR, IR, MS).