Chiral bioinspired iron complexes of N 4 ligands based on the ethylenediamine backbone display remarkable levels of enantioselectivity for the first time in the asymmetric epoxidation of a,b-unsaturated ketones using hydrogen peroxide (up to 87% ee) or peracetic acid as oxidant, respectively. Notablely, isotopic labeling with H 2 18O strongly demonstrated that there is a reversible water binding step prior to generation of the significant intermediate.usually derived from the decay of the LFe(IV)=O species or thermodynamic sinks for a number of iron complexes was identified by HR-MS. In addition, the possible mechanisms were proposed and LFe(V)=O species may be the main active intermediate in the catalytic system.

The first Pd-catalyzed direct phosphonation of azoles with dialkyl phosphites has been achieved without addition of base or acid. This method involves the oxidative cleavage of C-H and P(O)-H bonds and represents an atom-efficiency alternative to the classical phosphonation of Ar-X. A Pd(II)/Pd(IV) mechanism has been studied and proposed.

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