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Four silyl [P,Si]-chelate cobalt complexes ( 2- 5) have been synthesized through the chelate-assisted Si−H activation of bidentate preligand ortho-HSi(Me)2(PPh2)C6H4 ( 1) with CoMe(PMe3)4 and CoCl(PMe3)3. The silyl CoI complex, Co(PMe3)3(1-Si(Me)2-2-(PPh2)C6H4) ( 2), was synthesized by Si−H activation of 1 with CoMe(PMe3)4 or by combining complex 5 with MeLi and PMe3. Complex 2 was treated with CH3I or EtBr, generating the silyl CoII products CoI(PMe3)2(1-Si(Me)2-2-(PPh2)C6H4) ( 3) and CoBr(PMe3)2(1-Si(Me)2-2-(PPh2)C6H4) ( 4). The silyl CoIII hydride, CoHCl(PMe3)2(1-Si(Me)2-2-(PPh2)C6H4) ( 5), was obtained by the reaction of complex 1 with CoCl(PMe3)3. The catalytic performance of complex 5 was explored for Kumada coupling reactions, showing good to excellent catalytic efficiency with 2 mol % catalyst loading for the reactions of aryl chlorides or aryl bromides with Grignard reagents. It is noteworthy that the synthesis of 5 as a chelate complex is easier than that of previously reported [PSiP]-pincer cobalt hydride. With similar catalytic efficiency for Kumada reactions, the catalyst loading (2 %) of 5 was lower than that (5 %) of [PSiP]-pincer cobalt hydride. [ABSTRACT FROM AUTHOR]

The silver salts of 1-adamantanethiol (AdSH) and furan-2-ylmethanethiol (FurCH2SH) were successfully applied as building blocks for ligand-protected Ag2S nanoclusters. The reaction of the silver thiolates [AgSAd]x and [AgSCH2Fur]x with S(SiMe3)2 and 1,5-bis(diphenylphosphino) pentane (dpppt) afforded three different clusters with 58, 94 and, 190 silver atoms. The intensely colored compounds [Ag58S13(SAd)32] (1), [Ag94S34(SAd)26(dpppt)6] (2), and [Ag190S58(SCH2Fur)74(dpppt)8] (3) were structurally characterized by single-crystal X-ray diffraction and exhibit different cluster core geometries and ligand shells. The diameters of the well-defined sphere-shaped nanoclusters range from 2.2 nm to 3.5 nm. [ABSTRACT FROM AUTHOR]

An M4L4 type metal-organic cage (MOC-19) has been synthesized from the one-pot reaction of tri(pyridinylmethylene)phenylbenzeneamine (TPBA) with hydrated Zn(ClO4)2 under mild conditions and characterized by single-crystal X-Ray diffraction. Iodine capture studies show that the porous crystals of MOC-19 exhibit a versatile behavior to accumulate iodine species not only in vapor (for I2) but also in solution (for I2 and I3−), and anion-exchange experiments indicate the capacity to extract IO3− anions from aqueous solution. Enrichment of iodine species from KI/I2 aqueous solution proceeds facilely, revealing a pseudo-second-order kinetics of I3− adsorption. Furthermore, the electrical conductivity of MOC-19 single crystals could be significantly altered by I2 inclusion. [ABSTRACT FROM AUTHOR]