Platinum(ii) complexes of mixed-valent radicals derived from cyclotricatechylene, a macrocyclic tris-dioxolene.
Platinum(ii) complexes of mixed-valent radicals derived from cyclotricatechylene, a macrocyclic tris-dioxolene.
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DOI：
10.1039/c5sc02776d
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发表时间：
2015-12-01
期刊：
影响因子：
8.4
通讯作者：
Halcrow MA
中科院分区：
文献类型：
--
作者：
Loughrey JJ;Patmore NJ;Baldansuren A;Fielding AJ;McInnes EJL;Hardie MJ;Sproules S;Halcrow MA
用紫外/维斯/近红外光谱电化学、顺时针EPR、ENDOR和HYSCORE光谱和DF计算对氧化还原系列[1]0/1+/2+/3+进行了表征。合成了三种环三儿茶烯配合物[{PtL}3（μ3-ctc）]：（L = 1，2-双（二苯基膦基）苯{dppb}，1; L = 1，2-双（二苯基膦基）乙烷{dppe}，2; L = 4，4 ′-双（叔丁基）-2，2 ′-联吡啶{tBu 2bipy}，3）.配合物显示出三个低电位，化学可逆的伏安氧化分离的ca。180 mV，对应于[ctc]6-儿茶酚环逐步氧化至半醌水平。用紫外/维斯/近红外光谱电化学方法对氧化还原系列[1]0/1+/2+/3+和[3]0/1+/2+/3+进行了表征。一价和二价阳离子具有II类混合价特征，与类似的双二氧杂环戊烯系统相比，自由基离域减少。用顺式EPR、ENDOR和HYSCORE谱，借助于两个单稳态模型化合物[PtL（DBsq stec）]+（DBsqH = 3，5-二（叔丁基）-1，2-苯半醌; L = dppe或tBu_2bipy），确定了[1 stec]+和[3 stec]+的自组织轨道组成。DF和时间依赖性DF计算证实了这些解释，并证明了在CTC大环自旋离域的变化，因为它是顺序氧化。
The redox series [1]0/1+/2+/3+ has been characterised by UV/vis/NIR spectroelectrochemistry, cw EPR, ENDOR and HYSCORE spectroscopies and DF calculations. Three complexes of cyclotricatechylene (H6ctc), [{PtL}3(μ3-ctc)], have been synthesised: (L = 1,2-bis(diphenylphosphino)benzene {dppb}, 1; L = 1,2-bis(diphenylphosphino)ethane {dppe}, 2; L = 4,4′-bis(tert-butyl)-2,2′-bipyridyl {tBu2bipy}, 3). The complexes show three low-potential, chemically reversible voltammetric oxidations separated by ca. 180 mV, corresponding to stepwise oxidation of the [ctc]6– catecholato rings to the semiquinonate level. The redox series [1]0/1+/2+/3+ and [3]0/1+/2+/3+ have been characterised by UV/vis/NIR spectroelectrochemistry. The mono- and di-cations have class II mixed valent character, with reduced radical delocalisation compared to an analogous bis-dioxolene system. The SOMO composition of [1˙]+ and [3˙]+ has been delineated by cw EPR, ENDOR and HYSCORE spectroscopies, with the aid of two monometallic model compounds [PtL(DBsq˙)]+ (DBsqH = 3,5-bis(tert-butyl)-1,2-benzosemiquinone; L = dppe or tBu2bipy). DF and time-dependent DF calculations confirm these interpretations, and demonstrate changes to spin-delocalisation in the ctc macrocycle as it is sequentially oxidised.
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影响因子：
16.6
作者：
Abrahams, Brendan F.;Fitzgerald, Nicholas J.;Robson, Richard
通讯作者：
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影响因子：
4.6
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作者：
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影响因子：
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作者：
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通讯作者：
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影响因子：
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作者：
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通讯作者：
Sorace, Lorenzo