The electrophilic imino esters XF 2 CC(=NPG)CO 2 Me and imino phosphonates CF 3 CC(=NPG)P(O)(OR) 2 (PG = SO 2 Ph, Cbz, Boc) were transformed by nucleophilic and then electrophilic additions into fluorine-containing amino esters and amino phosphonates with two pendent alkene chains (XF 2 C)(CH 2 =CH(CH 2 ) n C(NPG)(Z)(CH 2 ) m CH=CH 2 [Z = CO 2 Me, P(O)(OR) 2 ]. The ring-closing metathesis was perfor-
Ferrocenium salts [(C5H5)2Fe]X (X = BF4, PF6) (I+·) react with tertiary phosphines PR3 (PMe3, PEt3, PnBu3, PMe2Ph, and PMePh2) in dichloromethane at room temperature to form a mixture of the corresponding ferrocenylphosphonium salts [(C5H5)FeC5H4PR3]X (III), ferrocene (I), and phosphonium salts [HPR3]X. The same reaction was carried out in an electrochemical cell as the electrolysis of a solution of ferrocene and phosphine in dichloromethane at the oxidation potential of ferrocene. Possible reaction pathways for phosphination of ferrocenium ion were studied by DFT at the M06‐L/6‐311++G(d,p) theory level. The experimental and theoretical studies of this reaction suggest it to proceed according to the Scheme of oxidative nucleophilic substitution of hydrogen in I+· including the following steps: a) nucleophilic exo addition of a phosphine to the cyclopentadienyl ring of I+· to form the radical cation adduct [(η5‐C5H5)Fe·(η4‐C5H5–+PR3)]X (II+·); b) redox reaction of the initial adduct II+· with the starting ferrocenium salt I+· to result in ferrocene (C5H5)2Fe (I) and iron phosphoniocyclopentadiene dication [(η5‐C5H5)Fe+(η4‐C5H5–+PR3)](X)2 (II2+) where the Csp3–H bond is involved in the agostic interaction with the metal atom; and c) deprotonation of the Csp3–H bond in II2+ by the starting phosphine to form III. The relation between the data obtained and current concepts of C–H functionalization in transition metal arene and cyclopentadienyl complexes is discussed.
o-Semiquinonic nickel pincer complexes (R2PCP)Ni(SQ) show a versatile coordination sphere dynamics via "swing" or "fan" oscillations depending on the steric properties of the phosphorus substituents.
Nucleophilic substitution of an iron(ii) dichloroclathrochelate with diphenylphosphine sulfide under PTC afforded a monophosphorylated cage complex. This precursor undergoes further nucleophilic substitution with mono- and diamines giving P,N-substituted mono- and bis-clathrochelates; those with thiophosphoryl and pyridyl groups were used as N,S-donor macrobicyclic ligands toward the palladium(ii) ion. In the resulting Pd,Fe-binuclear 1 : 1 complexes, the clathrochelate moieties retain the geometry, characteristic of low-spin iron(ii) complexes, with a minor distortion caused by intramolecular interactions. The Pd(2+) ion has a twisted square-planar N2SCl-environment. The complexes thus obtained proved to be efficient catalysts of the Suzuki cross-coupling reaction.
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