Iron complexes asymmetric hydrogenation

Scheme 13 Morris asymmetric hydrogenation catalyzed by iron complex 12...

Acyclic /V-alkylimines, asymmetric hydrogenation, 10, 56 Acyclic ( j3-allyl)cobalt complexes, oxidation reactions, 7, 58 Acyclic allylic esters, alkylation, 11, 76 Acyclic aromatic imines, asymmetric hydrogenation, 10, 56 Acyclic 1-buly l-( )5-pencadienyl) iron cations, preparation and reactivity, 6, 156... 

Preparative Methods by ring-closure of 3-bromobutyric acid with Sodium Carbonate, or by hydrogenation of Diketene. The optically active forms are obtained in the same manner starting from (J )- or (,S)-3-bromobutyric acid, which may be resolved with the (5) form of I-(I-Naphthyl)ethylamine Asymmetric aldol condensation using an enantiopure iron acetyl complex followed by cyclization, or asymmetric hydrogenation of diketene catalyzed by a chiral ruthenium complex, also gives the optically active p-lactone. 

Morris RH (2009) Asymmetric hydrogenation, transfer hydrogcaiation and hydrosilylation of ketones catalyzed by iron complexes. Chem Soc Rev 38 2282-2291... 

Dihydroboronium derivatives of t-Bu-BisP with different cotmter anions were prepared, as shown in Scheme 56. The reaction of BisP with BH2Br afforded the boronium salt 175 which possessed a bromide ion. The dihydroboronium derivative of (S,S)-l,2-bis(tert-butylmethylphosphino)ethane 175 (t-Bu-BisP ) was prepared by the reaction of t-Bu-BisP 174 with catecholborane and used as chiral diphosphine ligand precursor in Rh-catalyzed asymmetric hydrogenated of methyl (Z)-acetamidocinnamate to afford the hydrogenation product in up to 94% ee. Complexes of iron(III) and P-chiral phosphine oxides 176 are catalysts for the asymmetric Diels-Alder reaction of iV-acrylamide dienophiles [106]. 

The asymmetric epoxidation of acyclic )S,)3-disubstituted o, )3-enones in acetonitrile, by peracetic acid and catalysed by an iron complex in which Fe(OTf)2 was coordinated by two 2-[l-(l-naphthyl)-2-naphthyl]-l,10-phenanthroline ligands (35) (R = m-xylyl), to the corresponding Q ,j8-epoxyketones with yield up to 88% and up to 92% ee was achieved. The epoxy ketone was further converted to functionalized )8-keto-aldehydes with an all-carbon quaternary centre." The transfer hydrogenation of acetophenone to 1-phenylethanol in isopropanol in the absence of added base was catalysed by a five-coordinated Fe(II) complex (36) and certain analogues. ... 

F. 41 Asymmetric transfer hydrogenation of a [ o hinoyl imine using iron complex 14... 

The particular features of phosphonium salts were exploited for a number of synthetic applications in 2014. Phosphonium chloride salts found applications as chlorine source and as modifiers for homogeneous catalyst systems. As an example, Muller, Rosenthal and co-workers reported the study of a chromium-based catalyst for the selective tri-merization of ethylene. A phosphonium precursor of the type i cyclo-(PR2CH2CH(OH) )2][Br]2) was used for the preparation of iron(n) complexes containing unsymmetrical P-N-P pincer ligands (Scheme 5). The group of Prof. Morris tested these compounds as catalysts for the asymmetric hydrogenation of ketones and imines. ... 

Mikhailine A, Lough AJ, Morris RH. Efficient asymmetric transfer hydrogenation of ketones catalyzed by an iron complex containing a P-N-N-P tetradentate ligand formed by template synthesis. J Am Chem Soc. 2009 131(4) 1394—1395. 

The need in new inexpensive, safe and effective processes for asymmetric sulfide oxidations is determined by pharmaceutical industry requirements [38], Recently, inexpensive and active. systems based on hydrogen peroxide as oxidant and non-toxic chiral iron(III) complexes as catalysts have been reported [39-41 ]. Different mctal-salen complexes have also been previously employed as catalysts for oxidation of sulfides with PhIO Mn "(salen) [42-44], salen) 45], salen) [46], The mechanism proposed in [46] involves intermediate formation of 0x0 iron(lV)-salcn cation radical, that seems doubtful based on the experimental results obtained. In this Chapter we present asymmcinc version of the latter system [(salen )Fc ClJ/PhlO (where salcn stands for the corresponding chiral Schiff base ligands. Scheme 5) and an NMR investigation of the active intermediates. 

In the case of isomerization which proceeds according to the 7c-allyl mechanism, 1,3-hydrogen transfer takes place. These reactions are catalyzed by palladium(II) complexes which easily form 7r-allyl complexes from 7r-olefin compounds. Also, compounds of nickel, rhodium, iron, etc., are utilized as catalysts. Effective isomerization is possible if the hydrogen addition to both terminal carbon atoms of the 7r-allyl asymmetric grouping takes place. 

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