Catalytic Conversion of Alcohols into Carboxylic Acid Salts in Water: Scope, Recycling, and Mechanistic Insights.

The catalytic conversion of alcohols into carboxylic acid salts in water was performed in the presence of ruthenium complexes supported by aliphatic PNP pincer ligands preformed or formed in situ. High activity toward a wide substrate scope was achieved with turnover number values of up to 4000. The air-stable catalytic system can be recycled by using toluene as a catalyst-immobilizing phase; the activity is maintained after five consecutive runs.

Carbon dioxide induced phase switching for homogeneous-catalyst recycling.

SwitchPhos: Rhodium complexes formed from PPh(3) ligands functionalized with weakly basic amidine groups are highly active catalysts for the hydroformylation of alkenes. On bubbling with CO(2) in the presence of water, the yellow rhodium complexes move into the water phase, whereas bubbling with N(2) at 60 degrees C causes them to switch back into the organic phase. The catalysts can be used for reactions in water or an organic phase.

Aqueous-biphasic hydroformylation of higher alkenes promoted by alkylimidazolium salts.

Aqueous-biphasic hydroformylation of higher alkenes (>C5) can be greatly accelerated by addition of 1-octyl-3-methylimidazolium bromide without affecting the phase separation and with good catalyst retention in the aqueous phase.

A general ultrasound-assisted access to room-temperature ionic liquids.

The replacement of common organic solvents by room-temperature ionic liquids (RTILs) is a topical subject in both academia and industry. In the last decades, the number of applications for RTILs has followed an exponential curve and spilled over the boundaries of chemistry. Still, one of the main drawbacks of these compounds is their difficult access.