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RuCl2(PTA)4 (PTA=1,3,5‐triaza‐7‐phosphaadamantane) is an active, recyclable, air‐stable, aqueous‐phase nitrile hydration catalyst. The development of an in situ generated aqueous‐phase nitrile hydration catalyst (RuCl3⋅3 H2O+6 equivalents PTA) is reported. The activity of the in situ catalyst is comparable to RuCl2(PTA)4. The effects of [PTA] on the activity of the reaction were investigated: the catalytic activity, in general, increases as the pH goes up, which shows a positive correlation with [PTA]. The pH effects were further explored for both the in situ and RuCl2(PTA)4 catalyzed reaction in phosphate buffer solutions with particular attention given to pH 6.8 buffer. Increased catalytic activity was observed at pH 6.8 versus water for both systems with turnover frequency (TOF) up to 135 h−1 observed for RuCl2(PTA)4 and 64 h−1 for the in situ catalyst. Catalyst loading down to 0.001 mol % was examined with turnover numbers as high as 22 000 reported. Similar to the preformed catalyst, RuCl2(PTA)4, the in situ catalyst could be recycled more than five times without significant loss of activity from either water or pH 6.8 buffer. [ABSTRACT FROM AUTHOR]

Invited for the cover of this issue are the group of Raphaël Tripier and Nathalie Le Bris at the University of Brest (UMR CNRS 6521 CEMCA; France), Cathryn H. S. Driver from the South African Nuclear Energy Corporation in Pretoria (South Africa), and their collaborators. The image depicts the beginning of a new area of research into palladium and complexation of its radioisotopes for applications in nuclear medicine. Read the full text of the article at10.1002/chem.202200942. [ABSTRACT FROM AUTHOR]