Preparative Routes to Luminescent Mixed-Ligand Rhenium(I) Dicarbonyl Complexes

A series of mixed-ligand 2,2‘-bipyridine (bpy) and 1,10-phenanthroline (phen) rhenium(I) dicarbonyl complexes that
are emissive in fluid solution has been prepared, which includes a new class of the type cis-[Re(CO)2(P−P)(N−N)]+
(where P−P is a chelating diphosphine and N−N is a chelating polypyridine ligand). The four synthetic routes that
have been developed rely on either reactive triflate displacement or abstraction of labile chloro ligands, followed by
the use of the strong trans-labilizing effect of P donors or direct use of the trans effect of P donors. The spectroscopic,
photophysical, and electrochemical properties of these new complexes systematically vary with the net donor ability
of the ligands in the coordination sphere, as shown by correlations with Lever's EL parameters. Lifetimes and
quantum yields of the bipyridine complexes encompass a broad range, 25−1147 ns and ca. 0.002−0.11, respectively.

本研究制备了一系列在流体溶液中具有发射特性的混合配体2,2'-联吡啶(2,2'-bipyridine, bpy)与1,10-邻菲啰啉(1,10-phenanthroline, phen)合铼(I)二羰基配合物，其中包含一类新型顺式结构配合物cis-[Re(CO)2(P−P)(N−N)]+（其中P−P为螯合双膦配体(chelating diphosphine)，N−N为螯合多吡啶配体(chelating polypyridine ligand)）。已开发的四条合成路线均基于反应性三氟甲磺酸根取代反应，或是脱去易离去的氯配体，随后利用磷给体的强反位活化效应，或直接利用磷给体的反位效应。这类新型配合物的光谱学、光物理及电化学性质会随配位球内配体的净给电子能力发生系统性变化，该规律可通过与莱弗(Lever)EL参数的相关性得到验证。该系列联吡啶配合物的激发态寿命与量子产率覆盖较宽范围，分别为25~1147 ns和约0.002~0.11。