α-Amino Acids andN-Protected α-Amino Aldehydes by Stereoselective Additions of a Chiral Vinyllithium Reagent to Sulfonylimines
作者:Manfred Braun、Kersten Opdenbusch
DOI:10.1002/jlac.199719970121
日期:1997.1
proven by conversion into the oxazolidinones 16a–d whose optical purity is determined to exceed 92% e.e. by 1H-NMR measurements in the presence of chiralshiftreagents. The sulfonylimine 21a and a series of para-substituted derivatives 21b–h are also allowed to react with the vinyllithium reagent 1b to give mixtures of diastereomers 22/23. The logarithms of the diastereomeric ratios 22:23 correlate with
Synthesis, Self-Assembly, and Characterization of Supramolecular Polymers from Electroactive Dendron Rodcoil Molecules
作者:Benjamin W. Messmore、James F. Hulvat、Eli D. Sone、Samuel I. Stupp
DOI:10.1021/ja049325w
日期:2004.11.1
We report here the synthesis and self-assembly of a series of three molecules with dendron rodcoil architecture that contain conjugated segments of oligo(thiophene), oligo(phenylene-vinylene), and oligo(phenylene). Despite their structural differences, all three molecules yield similar self-assembled structures. Electron and atomic force microscopy reveals the self-assembly of the molecules into high