Visible-Light-Driven Tunable Molecular Motors Based on Oxindole
作者:Diederik Roke、Metin Sen、Wojciech Danowski、Sander J. Wezenberg、Ben L. Feringa
DOI:10.1021/jacs.9b03237
日期:2019.5.8
presented. This novel class of motors can be easily synthesized via a Knoevenagel condensation, and the choice of different upper halves allows for the facile tuning of their rotational speed. The four-step rotational cycle was explored using DFT calculations, and the expected photochemical and thermal isomerization behavior was confirmed by NMR, UV/vis, and CD spectroscopy. These oxindole motors offer
A supramolecularpolymer was constructed from a light-driven overcrowdedalkeneswitch modified with two alkylated gallic acid amide pendants (MSP-1). Upon UV irradiation, stable MSP-1 isomerized into unstable MSP-2, which induced the effective collapse of well-defined cross-linked supramolecularpolymers, and the reassembly can be realized by aging at low temperature.
N-Heterocyclic Carbene-Catalyzed Hydroacylation of Unactivated Double Bonds
作者:Keiichi Hirano、Akkattu T. Biju、Isabel Piel、Frank Glorius
DOI:10.1021/ja906361g
日期:2009.10.14
An intramolecular N-heterocyclic carbene (NHC)-catalyzed hydroacylation of unactivated double bonds is reported. Systematic variation of the catalyst structure revealed an N-mesitylthiazolylidene annulated with a seven-membered ring to be especially reactive. This NHC enables a unique C-C bond-forming reaction to afford substituted chroman-4-ones in moderate to excellent yields, even ones containing all-carbon quaternary centers.
Colonge; Guyot, Bulletin de la Societe Chimique de France, 1958, p. 325,328