Divergent Approach for Tris-Heteroleptic Cyclometalated Iridium Complexes Using Triisopropylsilylethynyl-Substituted Synthons.
Divergent Approach for Tris-Heteroleptic Cyclometalated Iridium Complexes Using Triisopropylsilylethynyl-Substituted Synthons.
复制标题
DOI：
10.1021/acs.organomet.2c00292
复制
发表时间：
2022-09-12
期刊：
影响因子：
2.8
通讯作者：
Davidson, Ross J.
中科院分区：
文献类型：
--
作者：
Edkins, Robert M.;Hsu, Yu-Ting;Fox, Mark A.;Yufit, Dmitry;Beeby, Andrew;Davidson, Ross J.
Ir（La）2（acac）形式的双杂配位环化铱配合物是一类有用的发光有机金属配合物，用于一系列应用，其中La是取代的2-苯基吡啶衍生物，acac是乙酰丙酮配体。相关的Ir（La）（Lb）（acac）形式的三混配配合物通过使用两种不同的环化配体提供了更大官能度的潜在优势，但通常更难以获得。我们报告的合成发散的双和三杂配三异丙基甲硅烷基乙炔基取代的中间络合物，可以多样化使用“化学上的复杂”的方法。我们通过一锅脱保护和Sonogashira交叉偶联的中间体配合物与对位-R-芳基碘（R = H，SMe和CN）的方法。比较了所得到的双和三混配配合物的物理和电化学行为，结果表明，三混配配合物表现出微妙的不同的发射和氧化还原性能的双混配配合物，如进一步红移发射最大值和较低的消光系数，这可以归因于减少对称性。它表明，支持DFT和含时DFT计算，发射的电荷转移字符可以通过改变终端取代基的变化而改变;在终端位置引入吸电子氰基导致显着的红移，而引入SMe基团可以大大增加发射量子产率。最值得注意的是，这种方便的合成方法减少了将三混配络合物分离成单一发散中间体的经常具有挑战性的需要，这将简化获得Ir（La）（Lb）（acac）形式的络合物家族。
Bis-heteroleptic cyclometalated iridium complexes of the form Ir(La)2(acac), where La is a substituted 2-phenylpyridine derivative and acac is an acetylacetonato ligand, are a useful class of luminescent organometallic complexes for a range of applications. Related tris-heteroleptic complexes of the form Ir(La)(Lb)(acac) offer the potential advantage of greater functionality through the use of two different cyclometalated ligands but are, in general, more difficult to obtain. We report the synthesis of divergent bis- and tris-heteroleptic triisopropylsilylethynyl-substituted intermediate complexes that can be diversified using a “chemistry-on-the-complex” approach. We demonstrate the methodology through one-pot deprotection and Sonogashira cross-coupling of the intermediate complexes with para-R-aryliodides (R = H, SMe, and CN). The photophysical and electrochemical behaviors of the resultant bis- and tris-heteroleptic complexes are compared, and it is shown that the tris-heteroleptic complexes exhibit subtly different emission and redox properties to the bis-heteroleptic complexes, such as further red-shifted emission maxima and lower extinction coefficients, which can be attributed to the reduced symmetry. It is demonstrated, supported by DFT and time-dependent DFT calculations, that the charge-transfer character of the emission can be altered via variation of the terminal substituent; the introduction of an electron-withdrawing cyano group in the terminal position leads to a significant red shift, while the introduction of an SMe group can substantially increase the emission quantum yield. Most notably, this convenient synthetic approach reduces the need to perform the often challenging isolation of tris-heteroleptic complexes to a single divergent intermediate, which will simplify access to families of complexes of the form Ir(La)(Lb)(acac).
登录
查看更多内容
影响因子：
4.6
作者：
Baranoff, Etienne;Curchod, Basile F. E.;Nazeeruddin, Md. Khaja
通讯作者：
Nazeeruddin, Md. Khaja
影响因子：
4.6
作者：
Davidson, Ross;Hsu, Yu-Ting;Beeby, Andrew
通讯作者：
Beeby, Andrew
影响因子：
4
作者：
Edkins, Robert M.;Wriglesworth, Alisdair;Beeby, Andrew
通讯作者：
Beeby, Andrew
影响因子：
4.6
作者：
Hisamatsu, Yosuke;Kumar, Sarvendra;Aoki, Shin
通讯作者：
Aoki, Shin
影响因子：
4.6
作者：
Lamansky, S;Djurovich, P;Thompson, ME
通讯作者：
Thompson, ME