Thermodynamic and electrochemical study of tailor-made crown ethers for redox-switchable (pseudo)rotaxanes
作者:Henrik Hupatz、Marius Gaedke、Hendrik V Schröder、Julia Beerhues、Arto Valkonen、Fabian Klautzsch、Sebastian Müller、Felix Witte、Kari Rissanen、Biprajit Sarkar、Christoph A Schalley
DOI:10.3762/bjoc.16.209
日期:——
Crown ethers are common building blocks in supramolecular chemistry and are frequently applied as cation sensors or as subunits in synthetic molecular machines. Developing switchable and specifically designed crown ethers enables the implementation of function into molecular assemblies. Seven tailor-made redox-active crown ethers incorporating tetrathiafulvalene (TTF) or naphthalene diimide (NDI) as
A Divalent Pentastable Redox-Switchable Donor-Acceptor Rotaxane
作者:Hendrik V. Schröder、Henrik Hupatz、Andreas J. Achazi、Sebastian Sobottka、Biprajit Sarkar、Beate Paulus、Christoph A. Schalley
DOI:10.1002/chem.201605710
日期:2017.2.24
resulting [2]rotaxane revealed the optoelectronic properties of an intramolecular charge transfer with a small HOMO–LUMO energy gap. Redox‐switching experiments showed the rotaxane to be pentastable. DFT calculations provided insights into the electronic structures of the five redox states.
Amine-promoted cyclocondensation of highly substituted aromatic nitrile oxides with diketones
作者:Jeffrey W Bode、Yoshifumi Hachisu、Tomoo Matsuura、Keisuke Suzuki
DOI:10.1016/s0040-4039(03)00614-2
日期:2003.4
Base-promoted cyclocondensation of hindered nitrileoxides and cyclic diketones affords highly functionalized, sterically-encumbered isoxazole products in good yield. The mild reaction conditions (NEt3, EtOH) are tolerant to a wide variety of functionality and permit the preparation of precursors to complex polycycles typically inaccessible via direct, intermolecular carboncarbon bond forming reactions
A click end-capping reaction exploiting nitrile N-oxide to rotaxane was described with emphasis of productivity of the protocol via stable C−C bond formation. Establishment of a pH-driven molecular shuttling system was also demonstrated by practical neutralization of the sec-ammonium group of the rotaxane axle with potassium hydroxide.
Exploring the nucleophilicity of<i>N</i>,<i>N</i>′-diamidocarbenes: Heteroallenes and related compounds as coupling reagents
作者:Young-Gi Lee、Jonathan P. Moerdyk、Christopher W. Bielawski
DOI:10.1002/poc.3004
日期:2012.11
The propensity of a stableN,N′‐diamidocarbene (DAC) to react with various heteroallenes was explored. The DAC condensed with 4‐nitrophenyl azide as well as 4‐nitrophenyl isothiocyanate to afford the respective acyclic triazene or zwitterionic dihydropyrimidinium imidothiolate products. Treating the DAC with two equivalents of 3‐nitrophenyl isocyanate afforded an iminooxazolidinone rather than the