The promising class of (polypyridine-ruthenium)-nitrosyl complexes capable of high yield Ru–NO/Ru–ON isomerization is targeted as a potential molecular device for the achievement of complete NLO switches in the solid state. A computational investigation conducted at the PBE0/6-31+G** DFT level for benchmark systems of general formula [R-terpyridine-RuIICl2(NO)](PF6) (R being a substituent with various donating or withdrawing capabilities) leads to the suggestion that an isomerization could produce a convincing NLO switch (large value of the βON/βOFF ratio) for R substituents of weak donating capabilities. Four new molecules were obtained in order to test the synthetic feasibility of this class of materials with R = 4′-p-bromophenyl, 4′-p-methoxyphenyl, 4′-p-diethylaminophenyl, and 4′-p-nitrophenyl. The different cis-(Cl,Cl) and trans-(Cl,Cl) isomers can be separated by HPLC, and identified by NMR and X-ray crystallographic studies.
能够进行高产率 Ru-NO/Ru-ON 异构化的(多
吡啶-
钌)-亚硝基配合物是一类很有前途的化合物,它是实现固态完全 NLO 开关的潜在分子装置。在 PBE0/6-31+G** DFT
水平上对通式为 [R-terpyridine-RuIICl2(NO)](PF6) 的基准体系(R 是具有各种捐赠或撤回能力的取代基)进行的计算研究表明,对于捐赠能力较弱的 R 取代基,异构化可以产生令人信服的 NLO 开关(βON/βOFF 比值较大)。为了测试这类材料的合成可行性,我们获得了四种新分子,R = 4′-对
溴苯基、4′-对
甲氧基苯基、4′-对二乙
氨基苯基和 4′-对
硝基苯基。不同的顺式(Cl,Cl)和反式(Cl,Cl)异构体可通过高效
液相色谱法分离,并通过核磁共振和 X 射线晶体学研究进行鉴定。