An explanation for the reversal in the sense of the enantioselectivity observed in hydrogen transfer reactions from 2‐propanol to ketones catalyzed by the ruthenium or osmium amino acidates [(η6‐p‐MeC6H4‐i‐Pr)M(Aa)Cl] and [(η6‐p‐MeC6H4‐i‐Pr)M(Aa)]3[BF4]3 [Aa=piperidine‐2‐carboxylate (pip), N‐methyl‐L‐phenylalaninate (MePhe)] is given; the molecular structures of [(η6‐p‐MeC6H4‐i‐Pr)Os(Pip)Cl] (1), [(η6‐p‐MeC6H4‐i‐Pr)Os(Pip)]3[BF4]3 (2), [(η6‐p‐MeC6H4‐i‐Pr)M(MePhe)Cl] [M=Ru (3), Os (4)] are also reported.

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The X-ray crystal structure of the potentially tridentate triallyl ligand [Fe(η5-C5H5){η6-(1,1-di(2-propenyl)-3-butenyl)benzene}][PF6] ([LFe][PF6]) (1) is reported. The reaction of 1 with [{Ir(μ-Cl)(cod)}2] yields the unusual five-coordinate cationic complex [(LFe)IrCl(cod)][PF6] (2), for which the 1H NMR COSY experiment and the X-ray crystal structure show the existence of two different types of allyl groups:  one free noncoordinated allyl and two bonded to Ir. The reaction of 2 with silver salts gives the square-planar complex [(LFe)Ir(cod)][PF6]2 (3) with the same trend of allyl coordination and displaying an NMR static behavior even at room temperature. Cyclic voltammetry of 1, 2, and 3 in DMF or MeCN on Pt at −40 °C shows a fully reversible FeII/I reduction wave, chemically fully irreversible FeI/0 reduction wave, and Ir oxidation wave, the latter being observed only for 2.

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