Living systems achieve sophisticated functions using supramolecular protein assemblies, in which the protein buildingblocks possess a specific secondary structure and are noncovalently arranged in a preprogrammed manner. Herein, we demonstrate the one-step synthesis of one-dimensional macromolecular assemblies by simply mixing a glycine-based isocyanide with a nickel catalyst, in which helical constituent
Chiral oxime ethers in asymmetric synthesis. O-(1-Phenylbutyl)benzyloxyacetaldoxime, a versatile reagent for the asymmetric synthesis of protected 1,2-aminoalcohols, α-amino acid derivatives, and 2-hydroxymethyl nitrogen heterocycles including iminosugars
作者:Tracey S. Cooper、Alexander S. Larigo、Pierre Laurent、Christopher J. Moody、Andrew K. Takle
DOI:10.1039/b500390c
日期:——
Addition of a range of organolithium and Grignard reagents to (E)-O-(1-phenylbutyl)benzyloxyacetaldoxime 1 in the presence of borontrifluoride diethyl etherate is highly diastereoselective. The resulting hydroxylamines undergo N-O bond cleavage upon treatment with zinc-acetic acid or molybdenum hexacarbonyl to give, after N-protection, protected 1,2-aminoalcohols 3 in high enantiomeric purity. Debenzylation
Enantioselective Rh-Catalyzed Hydrogenation of <i>N</i>-Formyl Dehydroamino Esters with Monodentate Phosphoramidite Ligands
作者:Lavinia Panella、Alicia Marco Aleixandre、Gerlof J. Kruidhof、Jort Robertus、Ben L. Feringa、Johannes G. de Vries、Adriaan J. Minnaard
DOI:10.1021/jo052451d
日期:2006.3.1
a range of aldehydes and with cyclohexanone. A highly convenient multigram scale one step synthesis of methyl 2-(formamido)acrylate was developed. This compound was used in the synthesis of methyl 2-(formamido)cinnamate via a solvent free Heck reaction. Moreover, full conversion and >99% ee were obtained in 1 h in the hydrogenation of methyl 2-(formamido)acrylate with 0.2 mol % catalyst and 2 bar hydrogen
Helical Assemblies of One-Dimensional Supramolecular Polymers Composed of Helical Macromolecules: Generation of Circularly Polarized Light Using an Infinitesimal Chiral Source
作者:Tomoyuki Ikai、Mitsuhiro Okubo、Yuya Wada
DOI:10.1021/jacs.9b13584
日期:2020.2.12
afforded sub-micrometer supramolecular fibers, in which almost perfect single-handed helical polyisocyanides were noncovalently connected end-to-end. The resulting helical supramolecularpolymers were further helically assembled to form a cholesteric liquid crystal film with an intense circularly polarized luminescence (CPL) signal. Surprisingly, the supramolecular system containing only 0.01 mol% of the