Catalytic Atroposelective Aerobic Oxidation Approaches to Axially Chiral Molecules
作者:Lenin Kumar Verdhi、Asit Ghosh、Natalia Fridman、Alex M. Szpilman
DOI:10.1021/acs.joc.3c00417
日期:2023.7.7
copper and chiral nitroxide co-catalyzed aerobic enantioselective oxidation process has been developed that allows access to axially chiral molecules. Two complementary atroposelective approaches, oxidative kinetic resolution (OKR) and desymmetrization, were studied using ambient air as the stoichiometric terminal oxidant. OKR of rac-N-arylpyrrole alcohols and rac-biaryl alcohols affords the optically
Extreme Projection of a Proton into the π-Cloud of an Aromatic Ring: Record Shielding of an Aromatic Proton in <i>trans</i>-10<i>b</i>-Methyl-10<i>c</i>-(1-naphthyl)-10<i>b</i>,10<i>c</i>-dihydropyrene
作者:Yuhua Ting、Yee-Hing Lai
DOI:10.1021/ja038380m
日期:2004.1.28
respectively. Both exhibit a strong diamagnetic ring current despite the introduction of an internal bulky substituent within the pi-electron cloud. Their electronic spectra suggest interaction between the two near-perpendicular naphthyl and dihydropyrenyl pi systems, resulting in red shift and band broadening. All naphthyl protons are well resolved in their 1H NMR spectra due to a strong shielding effect of