Supramolecular Bidentate Ligands by Metal-Directed in situ Formation of Antiparallel β-Sheet Structures and Application in Asymmetric Catalysis
作者:Andy C. Laungani、John M. Slattery、Ingo Krossing、Bernhard Breit
DOI:10.1002/chem.200800359
日期:2008.5.19
bidentate P-ligands for transition-metal catalysis, in which two complementary, monodentate, peptide-based ligands are brought together by employing peptide secondary structure motif as constructing tool to direct the self-assembly process, is achieved through formation of stable beta-sheet motifs and subsequent control of selectivity. The supramolecular structures were studied by (1)H, (31)P, and (13)C
Cooperative Effect of a Classical and a Weak Hydrogen Bond for the Metal-Induced Construction of a Self-Assembled β-Turn Mimic
作者:Andy C. Laungani、Manfred Keller、John M. Slattery、Ingo Krossing、Bernhard Breit
DOI:10.1002/chem.200900662
日期:2009.10.12
means of unprecedented multiple noncovalent interactions (classical hydrogenbond, weakhydrogenbond, metal coordination, π‐stacking interaction) was developed and investigated. Our results address the importance and capability of weakhydrogen bonds (WHBs) as important attractive interactions in self‐assembling processes based on molecularrecognition. Together with a classical hydrogenbond, WHBs may
Versatile Visible‐Light‐Driven Synthesis of Asymmetrical Phosphines and Phosphonium Salts
作者:Percia Beatrice Arockiam、Ulrich Lennert、Christina Graf、Robin Rothfelder、Daniel J. Scott、Tillmann G. Fischer、Kirsten Zeitler、Robert Wolf
DOI:10.1002/chem.202002646
日期:2020.12.9
Asymmetrically substituted tertiary phosphines and quaternaryphosphonium salts are used extensively in applications throughout industry and academia. Despite their significance, classical methods to synthesize such compounds often demand either harsh reaction conditions, prefunctionalization of starting materials, highly sensitive organometallic reagents, or expensive transition‐metal catalysts. Mild
of the library gave some excellent catalysts for regioselectivehydroformylation of β,γ‐unsaturatedcarboxylicacids. A terminal alkene, but‐3‐enoic acid, was hydroformylated with a linear/branched (l/b) regioselectivity up to 41. An internal alkene, pent‐3‐enoic acid was hydroformylated with regioselectivity up to 18:1. Further substrate selectivity (e.g., acid vs. methyl ester) and reaction site
Catalyst‐Free Visible Light Mediated Synthesis of Unsymmetrical Tertiary Arylphosphines
作者:Dmitry I. Bugaenko、Alexander V. Karchava
DOI:10.1002/adsc.202200309
日期:2022.7.5
Arylation of tertiary aryl and alkyl phosphines bearing 2-cyanoethyl group with aryl(mesityl)iodonium triflates under blue light irradiation followed by retro-Michael reaction of the in situ generated quaternaryphosphonium salts initiated by DBU represent a novel efficient and general method for the preparation of distinctly substituted tertiary arylphosphines. An operationally simple, one-pot protocol