Preparation and Study of Reusable Polymerized Catalysts for Ester Hydrogenation.

A cross-linked catalyst organic framework was prepared by an alternating ring-opening olefin metathesis polymerization between dichloro{,'-bis({(2-diphenylphosphino)phenyl}methylidene)bicyclo[2.2.1]-hept-5-ene-2,3-diamine}ruthenium, 1,2--di(-5-norbornene-2,3--dicarboximido)-ethane, and cyclooctene catalyzed by RuCl(=CHPh)(PCy) in the presence of a BaSO support.

Highly Enantioselective Hydrogenation of Amides via Dynamic Kinetic Resolution Under Low Pressure and Room Temperature.

High-throughput screening and lab-scale optimization were combined to develop the catalytic system trans-RuCl((S,S)-skewphos)((R,R)-dpen), 2-PrONa, and 2-PrOH. This system hydrogenates functionalized α-phenoxy and related amides at room temperature under 4 atm H pressure to give chiral alcohols with up to 99% yield and in greater than 99% enantiomeric excess via dynamic kinetic resolution.

Oxidation of the natural amino acids by a ferryl complex: kinetic and mechanistic studies with peptide model compounds.

Kinetic and mechanistic studies detailing the oxidation of substrates derived from the 20 natural amino acids by the ferryl complex [Fe(IV)(O)(N4Py)](2+) are described. Substrates of the general formula Ac-AA-NHtBu were treated with the ferryl complex under identical conditions ([Ac-AA-NHtBu] = 10 mM, [Fe] = 1 mM, 1:1 H(2)O/CH(3)CN), and pseudo-first-order rate constants were obtained. Relative rate constants calculated from these data illustrated the five most reactive substrates; in order of decreasing reactivity were those derived from Cys, Tyr, Trp, Met, and Gly.