Mono- and bimetallic pentacoordinate silicon complexes of a chelating bis(catecholimine) ligand
Mono- and bimetallic pentacoordinate silicon complexes of a chelating bis(catecholimine) ligand
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DOI：
10.1039/c9dt02475a
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发表时间：
2019-08-14
影响因子：
4
通讯作者：
Brown, Seth N.
中科院分区：
文献类型：
--
作者：
Do, Thomas H.;Brown, Seth N.
4,5-二氨基-9,9-二甲基杂蒽与4,6-二叔丁基儿茶酚-3-甲醛的席夫碱缩合得到双（儿茶酚亚胺）配体XbicH(4)，该配体可以结合双（儿茶酚）上袋和五边形N2O3下袋中的金属。与PhSiCl3金属化得到[(XbicH(2))SiPh][HCl2]，其中硅在上袋中采用五坐标方形金字塔几何结构，下袋与亚胺氮上的两个质子结合。亚胺与(LiOBu)-Bu-t, NaN[SiMe3](2)或AgOAc的脱质子作用导致单价金属离子在下袋中结合，在固体状态下采用不寻常的五边形单锥体几何形状。配合物表现出不可逆的电化学反应，在相对高的电位下发生氧化。
Schiff base condensation of 4,5-diamino-9,9-dimethylxanthene with 4,6-di-tert-butylcatechol-3-carboxaldehyde affords the bis(catecholimine) ligand XbicH(4), which can bind metals in both a square bis(catecholate) upper pocket and a pentagonal N2O3 lower pocket. Metalation with PhSiCl3 results in [(XbicH(2))SiPh][HCl2], where the silicon adopts a five-coordinate, square pyramidal geometry in the upper pocket and the lower pocket binds to two protons on the imine nitrogens. Deprotonation of the imines with (LiOBu)-Bu-t, NaN[SiMe3](2), or AgOAc results in binding of the univalent metal ion in the lower pocket, where it adopts an unusual pentagonal monopyramidal geometry in the solid state. The complexes show irreversible electrochemistry, with oxidations taking place at relatively high potentials.