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An efficient Pd-catalyzed asymmetric hydroesterification of vinyl arenes on water is reported. A variety of phenyl 2-arylpropanoates can be obtained in good yields with high b/l ratios and ee's with phenyl formate or CO as a carbonyl source. (R)-DTBM-SEGPHOS was found to be an effective ligand for the reaction under aqueous conditions. The hydrophobicity of the ligand appeared to be crucial to the hydroesterification reaction, which likely proceeded "on water". [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A Pd‐catalyzed regioselective hydroesterification of alkyl terminal olefins with aryl formates is described. A wide variety of linear carboxylic esters bearing various functional groups can be obtained in good yields with high regioselectivities under mild reaction conditions by using 1,2‐DTBPMB or (p‐F‐Ph)3P as ligand. The reaction process is operationally simple and requires no handling of toxic CO or strong acid. The resulting aryl esters can be readily converted to other carboxylic acid derivatives. [ABSTRACT FROM AUTHOR]

This work describes a copper‐catalyzed 8‐aminoquinoline‐assisted diamination of terminal olefins with di‐t‐butyldiaziridinone as nitrogen source, providing a variety of 2‐(2‐oxoimidazolidin‐4‐yl)‐N‐(quinolin‐8‐yl)acetamides in moderate to good yields. [ABSTRACT FROM AUTHOR]

Research has been conducted on the racemic enol ester epoxides. The kinetic resolution of these epoxides carried out via the chiral Lewis acid catalyzed rearrangement is described.

Research has been conducted on the chiral oxazolidinone ketone catalyst for asymmetric epoxidation. The role of electronic interactions in stereodifferentiation has been investigated via the mechanistic studies and the details are presented.

Research has been conducted on the enol esters. The epoxidation of these esters via fructose-derived chiral ketone as a catalyst and Oxone as an oxidant has been carried out and the results indicate that the acid-catalyzed rearrangement can proceed with the configuration retention and with the inversion.

The synthesis and catalytic properties of carbocyclic analogues of the fructose-derived ketones are presented. Data indicate that the asymmetric epoxidation of transolefins with the these ketones is low in terms of enantioselectivity and reactivity.

An efficient trifluoacetone (CF3COCH3)-catalyzed epoxidation using a hydrogen peroxide (H2O2) as primary oxidant at high pH, is reported. The usage of H2O2 as oxidant significantly reduces the amount of the solvent and salt introduced.

The enantioselective epoxidation of enynes using a fructose-derived ketone and the oxidant Oxone is described. This provides a direct route for synthesizing alkynyloxiranes.

The chiral ketone catalyzed asymmetric epoxidations of hydroxyalkenes were found to be highly pH dependent. The lower enantioselectivity at pH is due to the substantial contribution of the direct epoxidation by Oxone. At high pH, the epoxidation facilitated by chiral ketone becomes stronger than the racemic epoxidation, causing higher enantioselectivity. The effective substrates include allylic alcohol, homoallylic alcohol and bishomoallylic alcohol.

A highly effective and mild asymmetric monoepoxidation technique for conjugated dienes with a fructose-derived chiral ketone as catalyst and Oxone as oxidant is presented. The regioselectivities and enantioselectivities are very high for most cases. The regioselectivity can be controlled in unsymmetrical dienes, through steric and electronic regulation. The olefin substrates include trans-disubstituted and trisubstituted olefins that can withstand a broad range of functional groups such as hydroxyl groups, TBS ethers or esters.

Potassium peroxomonosulfate can be used as an oxidant and a fructose-derived ketone as a catalyst in an extremely effective catalytic asymmetric epoxidation method for olefins. It was found that pH is a vital factor for the expoxidation with dioxiranes generated in situ. In most cases, higher pH leads to quicker autodecomposition of potassium peroxomonosulfate, which in turn prompts a decrease in epoxidation efficiency. It is possible that the Baeyer-Villiger reaction is one of the key decomposition pathways for the catalyst.

The site-directed mutagenesis helps construct eleven Escherichia coli D-Ala-D-Ala ligase mutants. Kinetic studies help determine the activities of these mutants and the activities are compared with those predicted on the basis of X-ray structure. Kinetic studies of the inhibition of the activities of these mutants by a slow-binding phosphinate reveal that the inhibition is the highest for the S281A mutant.

Binding of cyclosporin A cyclophilin mutant of Escherichia coli F112W strain is homologous to human cyclophilin binding activity. A comparison of wild type E. coli cyclophilin and uncomplexed human cyclophilin reveals the difference in tryptophan 121 binding site of the two proteins, despite structural similarities at a pH of 6. 2.