Cover Picture: Syntheses and Catalytic Hydrogenation Performance of Cationic Bis(phosphine) Cobalt(I) Diene and Arene Compounds (Angew. Chem. Int. Ed. 27/2019)

Schrock–Osborn type cationic rhodium phosphine complexes, discovered and extensively studied since the 1970s, have formed the foundation of modern homogeneous and asymmetric catalysis. Cobalt, the first‐row congener of rhodium, is an attractive surrogate for this privileged class of catalysts, yet their cobalt analogues have remained elusive for over 40 years. In their Communication on page 9194 ff., P. J. Chirik and co‐workers report the first syntheses and characterization of these sought‐after cobalt complexes and their performance in asymmetric hydrogenation reactions.