Stereoselective Construction of Sterically Hindered Oxaspirocycles via Chiral Bidentate Directing Group-Mediated Csp−O Bond Formation Yechan Kim, Seoung-Tae Kim, Dahye Kang, Te-ik Sohn, Eunyoung Jang, MuHyun Baik,* and Sungwoo Hong* Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Korea Center for Catalytic Hydrocarbon Functionalizations, Inst...

An N-heterocyclic carbene (NHC)-catalyzed annulation reaction of isatin N-Boc ketimines and enals is developed for the synthesis of spirocyclic oxindole-γ-lactams bearing one quaternary chiral center in good yields and excellent stereoselectivities (up to >20:1 dr and 99% ee).

An efficient multi-component reaction to synthesize multi-substituted 1,3-oxazolidine compounds of high optical purity was described. All the products were well-characterized and the absolute configuration of one chiral center was determined. The plausible mechanism was proposed and a kinetic resolution of epoxides process was confirmed.

[reaction: see text] A concise stereoselective approach to the spirobicyclic imine fragment of pinnatoxins and pteriatoxins is described. The approach relies on a tandem reaction sequence involving consecutive sigmatropic rearrangements to build the quaternary chiral center at the core of the spirobicyclic ring system.

An efficient and environmentally friendly methodology for the solvent-free synthesis of α-amino nitrile derived ureas from α-amino acid based amino nitriles has been developed. At room temperature no epimerization was observed in the resulting ureas, but under microwave heating, epimerization occurred at the chiral center bearing the cyano group.

Stereospecific [3+2] cycloaddition of 1,2-cyclopropanated sugars and ketones catalyzed by SnCl4 is described. The method offers multi-substituted perhydrofuro[2,3-b]furans (bis-THFs) and perhydrofuro[2,3-b]pyrans containing a quaternary carbon chiral center in good to excellent yields.

Neutral Iridium Catalysts with Chiral Phosphine-Carboxy Ligands for Asymmetric Hydrogenation of Unsaturated Carboxylic Acids Shuang Yang, Wen Che, Hui-Ling Wu, Shou-Fei Zhu* and Qi-Lin Zhou* a State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, China b Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071, ...

We construct a novel observable for finite temperature QCD that relates confinement and chi-ral symmetry. It uses phases as boundary conditions for the fermions. We discuss numerical and analytical aspects of this observable, like its spectral behavior below and above the critical temperature, as well as the connection to chiral condensate and center symmetry.

We construct a novel observable for finite temperature QCD that relates confinement and chi-ral symmetry. It uses phases as boundary conditions for the fermions. We discuss numerical and analytical aspects of this observable, like its spectral behavior below and above the critical temperature, as well as the connection to chiral condensate, center symmetry and the canonical ensemble.