Pyridinedithioesters as Heterodienophiles: Application to the Synthesis of Aprikalim
摘要:
Pyridinedithioesters can be used as efficient heterodienophiles when activated by complexation with BF3, by protonation, or by oxidation of the nitrogen atom of the pyridine moiety. The hetero-Diels-Alder reaction using 3-pyridinedithioester as a heterodienophile was the key step in a new synthesis of Aprikalim in racemic form. The methodology can be reliably extended to prepare new analogues of Aprikalim.
Rational engineering of dimeric Dy-based Single-Molecule Magnets for surface grafting
作者:Xiaohui Yi、Fabrice Pointillart、Boris Le Guennic、Julie Jung、Carole Daiguebonne、Guillaume Calvez、Olivier Guillou、Kevin Bernot
DOI:10.1016/j.poly.2019.02.040
日期:2019.5
The deposition of Single-Molecule Magnets (SMMs) on surfaces is a mandatory step toward their possible use as data-storage units or qubits. In this study we report the structural and magnetic characterization of two parent compounds of a well-known SMM called DyPyNO, ([Dy(hfac)(3)(PyNO)](2) with hfac = hexafluoroacetylacetonate and PyNO = pyridine-N-oxide), that are targeted to be deposited on gold surfaces. Thio-substitution of the pyridine ring of these dimers is expected to provide good anchoring group toward deposition on gold. We have investigated two significantly different geometries of the anchoring groups in dimers 1 and 2. Interestingly, despite these strong differences, SMM behavior is remarkably well-preserved in the polycrystalline material offering possibilities to graft these SMMs on surface. (C) 2019 Elsevier Ltd. All rights reserved.