Diphenylamine-Substituted Osmanaphthalyne Complexes: Structural, Bonding, and Redox Properties of Unusual Donor-Bridge-Acceptor Systems
Diphenylamine-Substituted Osmanaphthalyne Complexes: Structural, Bonding, and Redox Properties of Unusual Donor-Bridge-Acceptor Systems
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二苯胺取代的桂萘配合物：异常供体-桥-受体系统的结构、键合和氧化还原特性
DOI：
10.1002/chem.201804025
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Liu Sheng Hua
中科院分区：
文献类型：
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作者：
Zhang Ming Xing;Zhang Jing;Jin Xuyang;Sun Xiaona;Yin Jun;Hartl Frantisek;Liu Sheng Hua
合成了由金属环(C^C+)刚性骨架连接的两个氧化还原中心相连的二芳胺取代月桂醇配合物[OsCl2(PPh3)2{(C^C+)NAr2}][BF4−](Ar=Ph(1 a)，p-MeOPh(1 b))及其开环前驱体[OsHCl2(PPh3+)2{(≡C−C(PPh3+)=CHPh)NR2}][BF4−](Ar=Ph(2 a)，p-MeOPh(2 b))，并用1H，13C和31P 谱、ESI-MS和元素分析进行了表征.用单晶X-射线衍射法确定了配合物1- 和2- 的固态分子结构。两个配合物1-≡和2- 中的Os- -C键长均在报道的类似桂冠杂环化合物和奥卡宾配合物的范围内。通过理论计算成功地再现了配合物1 a的结构参数，这些参数指向π离域金属循环结构。化合物1 A和B的紫色是由二芳胺→Os(金属环)在可见光区的电荷转移吸收解释的。用循环伏安法、方波伏安法、UV/Vis/近红外光谱电化学和密度泛函理论研究了化合物1 a，b和缺少二芳胺取代基的参比配合物[OsCl2(PPh3)2{(C^C+)}][BF4−](1‘)的中性、单电子氧化和单电子还原状态。单氧化配合物[1 a]+和[1 b]+的自旋密度主要分布在氨基链段上，其中Os的参与受二苯胺取代的控制。稳定的、单一还原的[1‘]−中的自旋密度主要分布在月桂醇金属循环中。
Diarylamine‐substituted osmanaphthalyne complexes that feature two redox centers linked by the rigid skeleton of the metallacycle (C^C+), specifically, [OsCl2(PPh3)2{(C^C+)NAr2}][BF4−] (Ar=Ph (1 a),p‐MeOPh (1 b)) and their open‐ring precursors [OsHCl2(PPh3)2{(≡C−C(PPh3+)=CHPh)NR2}][BF4−] (Ar=Ph (2 a),p‐MeOPh (2 b)), were successfully synthesized and characterized by1H,13C, and31P NMR spectroscopy, ESI‐MS, and elemental analysis. The solid‐state molecular structures of complexes1 aand2 awere ascertained by single‐crystal X‐ray diffraction. The Os≡C bond length in both complexes1 aand2 afell within the range reported for similar osmanaphthalynes and osmium carbyne complexes, respectively. The structural parameters determined for complex1 a, which were successfully reproduced by theoretical calculations, point to a π‐delocalized metallacycle structure. The purple color of compounds1 aandbwas explained by the diarylamine→Os(metallacycle) charge‐transfer absorption in the visible region. The neutral, one‐electron‐oxidized and one‐electron‐reduced states of compounds1 a,b, and a reference complex that lacked the diarylamine substituent, [OsCl2(PPh3)2{(C^C+)}][BF4−] (1′), were investigated by cyclic and square‐wave voltammetry, UV/Vis/NIR spectroelectrochemistry, and DFT calculations. The spin density in singly oxidized complexes [1 a]+and [1 b]+predominantly resided on the aminyl segment, with osmium involvement controlled by the diphenylamine substitution. Spin density in stable, singly‐reduced [1′]−was distributed mainly over the osmanaphthalyne metallacycle.