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A set of antimony(III) compounds containing a ligand (Ar) with a pendant guanidine function (where Ar = 2-[(Me2N)2C N]C6H4) was prepared and characterized. This includes triorgano-Ar3Sb, diorgano-Ar2SbCl and monoorgano-ArSbCl2 compounds and they were characterized by ¹H and 13C NMR spectroscopy and by single-crystal X-ray diffraction analysis (sc-XRD). The coordination capability of Ar3Sb and Ar2SbCl was examined in the reactions with either cis-[PdCl2(CH3CN)2] or PtCl2 and complexes cis-[(κ²-Sb,N-Ar3Sb)MCl2] (M = Pd 1, Pt 2) and [(κ³-N,Sb,N-Ar2SbCl)MCl2] (M = Pd 3, Pt 4) were isolated, while their structures were determined by sc-XRD. Notably, the ligands Ar3Sb and Ar2SbCl exhibit different coordination modes - bidentate and tridentate, respectively - and the antimony exhibits three distinct bonding modes in complexes 1-4, which were also subjected to theoretical studies. [ABSTRACT FROM AUTHOR]

The coordination capability of two N,C,N pincer coordinated stibinidenes, i. e. bis(imino)‐ [2,6‐(DippN=CH)2C6H3]Sb (1) or imino‐amino‐ [2‐(DippN=CH)‐6‐(DippNHCH2)C6H3]Sb (2) toward palladium(II) and platinum(II) centers was examined. In the course of this study, seven new square‐planar bis(stibinidene) complexes were synthesized and characterized by NMR, IR, Raman, UV‐vis spectroscopy and single crystal (sc)‐X‐ray diffraction analysis. In all cases, both stibinidene ligands 1 or 2 adopt trans positions, but differ significantly in the torsion angle describing mutual orientation of aromatic rings of the stibinidenes along the Sb−Pd/Pt−Sb axes. Furthermore, majority of complexes form isomers in solution most probably due to a hindered rotation around Sb−Pd/Pt bonds caused by bulkiness of 1 and 2. This phenomenon also seems to be influenced by the absence/presence of a pendant −CH2NH− group in 1/2 that is able to form intramolecular hydrogen bonds with the adjacent chlorine atom(s) attached to the metal centers. The whole problem was subjected to a theoretical study focusing on the role of hydrogen bonds in structure architecture of the complexes. To describe the UV‐vis spectra of these highly coloured complexes, TD‐DFT calculations were employed. These outline differences between the stibinidene ligands, the transition metals as well as between the charge of the complexes (neutral or anionic). [ABSTRACT FROM AUTHOR]

In this study, Ru complexes [(η6‐p‐cymene)RuX(2‐{(2,6‐iPr2‐C6H3)N=CH}‐C5H3N‐6‐(O))] (3: X=Cl; 4: X=I) were prepared with N‐bound 2‐pyridonato ligand by thermal base‐free MeX elimination from ionic N,N‐chelated Ru complexes [(η6‐p‐cymene)RuX(κ2‐L1)](X) (1: X=Cl; 2: X=I; L1={2‐[(2,6‐iPr2‐C6H3)N=CH]‐6‐(OMe)C5H3N}). The Ru complex 3 was used as O‐donor for Lewis (LA) or Brönsted acids. The reactions of 3 with SnCl2, Ph3SnCl, ZnCl2 or HCl provided [(η6‐p‐cymene)Ru(SnCl3)(2‐{(2,6‐iPr2‐C6H3)N=CH}‐C5H3N‐6‐(O→SnCl2)] (6), [(η6‐p‐cymene)RuCl(2‐{(2,6‐iPr2‐C6H3)N=CH}‐C5H3N‐6‐(O→SnPh3Cl)] (7), and [(η6‐p‐cymene)RuCl(2‐{(2,6‐iPr2‐C6H3)N=CH}‐C5H3N‐6‐(O→)]2(μ‐ZnCl2) (8) and [(η6‐p‐cymene)RuCl(2‐{(2,6‐iPr2‐C6H3)N=CH}‐C5H3N‐6‐(OH)}](Cl) (9). The easy conversion of the 2‐pyridonato ligand in 3 to its 2‐hydroxypyridine in 9 evoked testing of 3 and 4 as potential catalysts in base‐free transfer‐hydrogenation of ketones. [ABSTRACT FROM AUTHOR]

This study reports the synthesis and characterization of new molybdenum compounds bearing benz[e]indenyl and benz[f]indenyl ligands. The capability of the ligands to undergo η5-to-η3 haptotropic rearrangement was evidenced on reactions with tris(pyrazolyl)methane. Appearance of the η3-coordination mode was determined by NMR spectroscopy and X-ray structure analysis on a single crystal. [ABSTRACT FROM AUTHOR]

1-Boryl-8-phosphinonaphthalenes 1-BCy2-8-PCl2-C10H6 (1) and 1-BCy2-8-PPhCl-C10H6 (2) were prepared and used as starting materials for the synthesis of B-substituted phosphides. The reduction of 1 and 2 by Mg provided neutral compounds [1-BCy-8-PCy-C10H6]2 (3) and [1-BCy2-8-PPh-C10H6]2 (4). Compound 3 represents the dimer of phosphinoborane 1-BCy-8-PCy-C10H6 while complex 4 is a rare example of a discrete B ← P coordinated diphosphine. The reduction of 2 by Na or K in THF yielded B-substituted group 1 phosphides [Na(THF)3]+[1-BCy2-8-PPh-C10H6]− (5) and {[K(THF)2]+[1-BCy2-8-PPh-C10H6]−}∞ (6), which structurally resembled bulky group 1 phosphides. Complex 5 showed easy activation of elemental chalcogens E (E = O, S, Se) to give B-substituted chalcogenophosphinites {[Na(THF)2]+[1-BCy2-8-P(E)Ph-C10H6]}2 (E = O (7), S (8), Se (9)) as the products of chalcogen insertion into the P–Na bond. Importantly no oxidation to dichalcogenophosphinates was observed. Compound 5 is tolerant of the CO polar bonds in organic substrates and the reactions of 5 with 2,3-butanedione or an acyl chloride provided {[Na(THF)2]+[1-BCy2-8-P{CHC(O)C(Me)O}Ph-C10H6]−}2 (10) and [1-BCy2-8-P{C(O)tBu}Ph-C10H6] (11). Finally, B-coordinated phosphatetrylenes [1-BCy2-8-P(SnL)Ph-C10H6] (12) and [1-BCy2-8-P(PbL)Ph-C10H6] (13) (L is {2,6-(Me2NCH2)C6H3}−) were also prepared by substitution reactions of 5. [ABSTRACT FROM AUTHOR]

N‐coordinated Ge(II) alkoxides L1(tBuO)Ge (1), L2(tBuO)Ge (2) and [L2(OtBu)Ge ⋅ BH3] (4) were prepared. Effect of either chelating ligands L1 and L2 or Ge→B interaction on strength of the Ge−OtBu bond was studied by insertion reaction of PhNCO. As a result, the Ge(II) carbamate L2{[(tBuO)OC](Ph)N}Ge (3) was isolated. Alcoholysis exchange reactions of 1 and 2 with substituted phenols were studied to find an easy synthetic protocol for a synthesis of functionalized Ge(II) alkoxides. Reactions yielded Ge(II) alkoxides L1,2(2‐Br−C6H4O)Ge (5 for L1, 8 for L2), L1,2(2‐MeNH−C6H4O)Ge (6 for L1, 9 for L2), L1,2(2‐Ph2P−C6H4O)Ge (7 for L1, 10 for L2), L2(2‐Br‐3‐OH−C6H3O)Ge (11) and L2(2‐NC5H4O)Ge (12) containing the additional polar groups Y (Y=Br, MeNH, PPh2, OH or N). Finally, phosphane decorated Ge(II) alkoxides 7 and 10 were tested as suitable ligands in reactions with (COD)W(CO)4 and BH3. As a consequence, new complexes [(κ2‐7)W(CO)4] (13) and [L1(2‐Ph2P ⋅ {BH3}‐C6H4O)Ge ⋅ {BH3}] (14) were isolated. All compounds were characterized by NMR and IR spectroscopy, and compounds 3, 4, 9 and 11 were additionally characterized by X‐ray diffraction analysis. [ABSTRACT FROM AUTHOR]