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The systematic exploration of the modification of polyethylene imine with guanidinium and octyl groups has led to the identification of a catalyst, CD6, which accelerates the phosphate transfer reaction of HPNP (2‐hydroxypropyl‐4‐nitrophenyl phosphate) in the presence of divalent metals such as Zn2+, Co2+, Mg2+or Ni2+. CD6 exhibits saturation kinetics that are described by Michaelis–Menten parameters Kmranging from 2.5–8 mMand kcatranging from 0.0014–0.09 s−1. For ZnII–CD6 this corresponds to an overall acceleration kcat/kuncatof 3.8×105and a catalytic proficiency (kcat/Km)/kuncatof 1.5×108. Catalysis by ZnII–CD6 is specifically inhibited by inorganic phosphate, allowing turnover regulation by product inhibition. This effect stands in contrast to ZnII‐catalysed transesterification of HPNP in water or by the synzymes CoII–CD6 and NiII–CD6, with which no such interference by product is observed. These characteristics render synzyme ZnII–CD6 an efficient enzyme model that reflects enzyme‐like properties in a wide range of features.

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In the presence of hydrogen peroxide, m-chloroperbenzoic acid or an iodosyl arene, the tert-butyl group of the ligand HL–t-Bu in the complex Fe2L–t-Bumpdp2is quantitatively hydroxylated to a butanolate terminally bound to one iron in Fe2L–t-Bu − H Ompdp2, and mass spectrometry experiments indicate that the reaction proceeds according to different mechanisms.

In the presence of oxygen atom donors [XO, e.g., m-chloroperbenzoic acid m-CPBA, o-tert-butylsulfone iodosyl benzene ArIO] the benzyl group of the ligand in a mixed-valent FeiiFeiiicomplex is almost quantitatively ortho-hydroxylated to a phenolate terminally bound to one iron in the derived FeiiiFeiiicomplex. All available experimental evidence concurs to suggest that this reaction involves an oxo-FeivFeivintermediate.

In the presence of oxygen atom donors [XO, e.g., m-chloroperbenzoic acid (m-CPBA), o-tert-butylsulfone iodosyl benzene (ArIO)] the benzyl group of the ligand in a mixed-valent FeiiFeiii complex is almost quantitatively ortho-hydroxylated to a phenolate terminally bound to one iron in the derived FeiiiFeiii complex. All available experimental evidence concurs to suggest that this reaction involves an oxo-FeivFeiv intermediate.

A non-heme iron complex catalyses the aziridination of various olefins and the amidation of thioanisole in good yields at the expense of an aryl iodinane.

A non-heme iron complex catalyses the aziridination of various olefins and the amidation of thioanisole in good yields at the expense of an aryl iodinane.