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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Coordination complexes with the redox active tetrathiafulvalene based imino-pyrazine ligand: syntheses, a radical
Goulven Cosquer1, Fabrice Pointillart, Yann Le Gal
1Organométalliques et Matériaux Moléculaires, UMR 6226 CNRS-UR1 Sciences Chimiques de Rennes, Université de Rennes 1, 35042 Rennes Cedex, France.
Abstract:
The tetrathiafulvalene based 2-immino-pyrazine derivative (TTF-CHN-2-pyz) () was synthesized and characterized. Its radical cation salt ( (+)PF(6)(-)) was prepared as single crystals by electrocrystallisation. (+)PF(6)(-) crystallizes in the triclinic P1 space group. Four 1 : 2 bis(hexafluoroacetylacetonate)M(ii) complexes coordinated with were prepared (M = Mn for , M = Co for , M = Cu for and M = Zn for ). Complex crystallizes in the monoclinic C2/c space group, complexes and crystallize in the triclinic space group P1. Two pyrazine N atoms from two different donors are coordinated in cis configuration for and trans configuration for and to the metallic ion of M(hfac)(2) (hfac(-)=hexafluoroacetylacetonate anion). The manganese atom adopts a pseudo-compressed octahedral geometry while the copper and the zinc ions adopt axially elongated octahedral geometries. Both crystal packing structures and electrochemical properties are appropriate for their potential use as starting molecular bricks for conducting and magnetic materials.
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