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Reactivity studies of the GeII→B complex L(Cl)Ge⋅BH3 (1; L=2‐Et2NCH2‐4,6‐tBu2‐C6H2) were performed to determine the effect on the GeII→B donation. N‐coordinated compounds L(OtBu)Ge⋅BH3 (2) and [LGe⋅BH3]2 (3) were prepared. The possible tuning of the GeII→B interaction was proved experimentally, yielding compounds 1‐PPh2‐8‐(LGe)‐C10H6 (4) and L(Cl)Ge⋅GaCl3 (5) without a GeII→B interaction. In 5, an unprecedented GeII→Ga coordination was revealed. The experimental results were complemented by a theoretical study focusing on the bonding in 1−5. The different strength of the GeII→E (E=B, Ga) donation was evaluated by using energy decomposition analysis. The basicity of different L(X)Ge groups through proton affinity is also assessed. [ABSTRACT FROM AUTHOR]

The pnictogenyl Group 13 compounds (Dipp2Nacnac)M[E(SiMe3)2]Cl and (Dipp2Nacnac)M(EH2)2 (Dipp2Nacnac=HC[C(Me)N(Ar)]2, Ar: Dipp=2,6‐iPr2C6H3; M=Al, Ga, In; E=P, As) were successfully synthesized. The salt metathesis between (Dipp2Nacnac)MCl2 and LiE(SiMe3)2 only led to monosubstituted compounds (Dipp2Nacnac)M[E(SiMe3)2]Cl [E=P, M=Ga(1), In (2); E=As, M=Ga (3), In (4)], regardless of the stoichiometric ratios used. In contrast to the steric effect of the SiMe3 groups in 1–4, the reactions of the corresponding halides with LiPH2⋅DME (or KAsH2) facilely yielded the dipnictogenide compounds (Dipp2Nacnac)M(EH2)2 (E=P, M=Al (5), Ga (6), In (7); E=As, M=Al (8), Ga (9)), avoiding the use of flammable and toxic PH3 and AsH3 for their synthesis. The compounds 5–9 are the first examples of monomeric Group 13 diphosphanides and diarsanides in which the metal center is bound to two terminal PH2 and AsH2 groups, respectively. In contrast to the successful synthesis of the indium diphosphanide (Dipp2Nacnac)In(PH2)2, the reaction of (Dipp2Nacnac)InCl2 with KAsH2 led to an indium mirror due to the instability of the target product. [ABSTRACT FROM AUTHOR]

Graphical abstract Six compounds of bis(iminophosphorano)methanide chelate ligand was synthesized and the compounds either present the intramolecular C Al σ bond or C− M+ ionic bonding interactions. Abstract The organolithium bis(iminophosphorano)methandiide dimer [Li 2 C(Ph 2 P NSiMe 3) 2 ] 2 ([Li 2 - 1 ] 2) reacts with 4 equiv of AlCl 3 in THF to generate the novel bimetallic aluminum carbene complex of [Li(THF) 4 ][{C(Ph 2 P NSiMe 3) 2 }Al 2 Cl 5 ] (1). In addition, several new bis(iminophosphorano)methanide chelate-coordinated complexes of [{CH(Ph 2 P NSiMe 3) 2 }AlCl 2 ] (2) , [{CH(Ph 2 P NSiMe 3) 2 }GaBr 2 ] (3) , [{CH(Ph 2 P NSiMe 3) 2 }InCl 2 ] (4) , and [{CH(Ph 2 P NSiMe 3) 2 }InBr 2 ] (5) are synthesized in situ while organolithium bis(iminophosphorano)methandiide ([Li 2 - 1 ] 2) reacts with 2 equiv of metal halides AlCl 3 , GaBr 3 InCl 3 and InBr 3 respectively in THF. Furthermore, an unexpected complex of [{CH 2 (Ph 2 P NSiMe 3) 2 }ZnCl 2 ] (6) is formed as [Li 2 - 1 ] 2 dimer reacted with 2 equiv of ZnCl 2 in situ. All six synthesized complexes (1 , 2 , 3 , 4 , 5 and 6) in situ were isolated in solid and were structurally characterized by X-ray diffraction. Complexes containing particular carbene to metal or ionic linking interaction bonds (1 , 2 , 3 and 4) were selected and further characterized in detail by DFT calculations using Gaussian03 program. The DFT calculation demonstrates the existence of a carbene Al σ bond in structure 1 and ionic linkage interaction in structures 2 – 4. [ABSTRACT FROM AUTHOR]

The structure of the title compound, [Al2(OH)2(C6H12N2O)6]I4·4C6H12N2O (systematic name: di-μ2-hydroxido-bis{tris[1,3-dimethyltetrahydropyrimidin-2(1H)-one-κO]aluminium} tetraiodide 1,3-dimethyltetrahydropyrimidin-2(1H)-one tetrasolvate), is composed of two Al(C6H12N2O)3 moieties linked into a centrosymmetric dinuclear unit by a pair of bridging hydroxide ions. The aluminium cations show a distorted trigonal bipyramidal AlO5 coordination environment formed only by monodentate ligands. The Al—O bond lengths are in the range 1.789 (2)–1.859 (2) Å (mean bond length = 1.818 Å). The non-coordinating iodide anions compensate the charge of the complex cation. The remaining solvent molecules and the iodide counter-anions interact with the complex cation by weak non-classical C—H...I and C—H...O hydrogen bonds.

We report the synthesis of a gallium complex incorporating redox-active pyridyl nitroxide ligands. The (pyNO−)2GaCl complex was prepared in 85% yield via a salt metathesis route and was characterized by 1H and 13C NMR spectroscopies, X-ray diffraction, and theory. UV–Vis absorption spectroscopy and electrochemistry were used to access the optical and electrochemical properties of the complex, respectively. Our discussion focuses primarily on a comparison of the gallium complex to the corresponding aluminum derivative and shows that although the complexes are very similar, small differences in the electronic structure of the complexes can be correlated to the identity of the metal.

1-(1,3-Benzothiazol-2-ylsulfanyl)propan-2-ol (C 10 H 10 NS 2 OH, LH) was used as a multifunctional ligand in reactions with aluminum trialkyls R 3 Al (R = i Bu, Et, t Bu). The reactions at 1:1 M ratio of reagents proceeded with formation of dimeric (R 2 AlL) 2 (R = i Bu, Et) complexes with a central Al 2 O 2 ring, whereas in a presence of an excess of R 3 Al the compounds [(R 2 Al)(R 3 Al)L] 2 (R = i Bu, Et) with the central Al 2 O 2 ring and R 3 Al molecules coordinated to nitrogen atoms were obtained. i Bu 3 Al reacted with the LH yielding monomeric complex t Bu 2 AlL independently on the molar ratio of reagents. In the compound, Al coordinates to the nitrogen atom to form intramolecular sp 2 -N donor bonding. The compounds [( i Bu 2 Al)( i Bu 3 Al)L] 2 ( 1 ), (Et 2 AlL) 2 ( 2 ) and t Bu 2 AlL ( 3 ) were synthesized as pure compounds and characterized. Among four heteroatoms of the ligand, only the oxygen and nitrogen atoms can form bonds with aluminum atoms, whereas two sulfur atoms are non-coordinative. The compounds 1 and 2 are active as an initiator of the ε-caprolactone polymerization. [ABSTRACT FROM AUTHOR]

Two aspects of Group 13 metal chemistry are surveyed in the light of recent matrix-isolation and quantum chemical studies. The first concerns derivatives of the metals Al, Ga and In (M) in formal oxidation states less than +3: these include the M0 derivatives MLn, where L=CO, N2, NH3 or PH3, and n=1 or 2; the MI derivatives MX, where X=H, CH3 or NH2, and M2H2; and the MII derivatives HMX, where X=H, CH3, NH2 or PH2. The second concerns derivatives in which there is the opportunity for the metal to engage in multiple bonding, as exemplified by the cases of M2H2 and H2MNH2. Experimental studies have involved thermally or photolytically excited reactions between M atoms, or sometimes M2 molecules, and an appropriate substrate, e.g. H2, CO, N2, CH4, NH3 or PH3. The reagents have been trapped in solid noble gas matrices, the IR spectra of which have been exploited to deduce the course of events and identities of the products. Confirmation of the identity and geometry of each of the products have been achieved primarily on the basis (i) of isotopic effects and (ii) of comparison of the measured spectrum with that anticipated by quantum chemical calculations. This liaison of experiments with theory has led to the characterisation not only of numerous simple molecules that are short-lived under normal conditions, but also of some of the reaction channels open to them, typically through photolytic activation. The structure, energies and reactivities of the compounds are reviewed. [Copyright &y& Elsevier]

This paper surveys the structures and chemical bonding in several recently discovered organometallic gallium and indium clusters including the tricapped trigonal prism Ga9(CMe3)9, the bicapped octahedron In8[Si(CMe3)3]6, fused deltahedra such as Ga10[Si(SiMe3)3]6 and In12[Si(CMe3)3]8, and the more complicated supraicosahedral structures [Ga19{C(SiMe3)3}8]2−, Ga22[Si(SiMe3)3]8, and Ga26[Si(SiMe3)3]82−. The Wade–Mingos 2n+2 and Jemmis 2n+2m electron-counting rules appear to be applicable to most of these clusters. The deltahedra found in the supraicosahedral Group 13 metal clusters can be derived from the 12-vertex cuboctahedron and related 13-vertex polyhedra by capping all of the non-triangular faces. [Copyright &y& Elsevier]

The pnictogenyl Group 13 compounds (Dipp 2 Nacnac)M[E(SiMe 3 ) 2 ]Cl and (Dipp 2 Nacnac)M(EH 2 ) 2 (Dipp 2 Nacnac=HC[C(Me)N(Ar)] 2 , Ar: Dipp=2,6-iPr 2 C 6 H 3 ; M=Al, Ga, In; E=P, As) were successfully synthesized. The salt metathesis between (Dipp 2 Nacnac)MCl 2 and LiE(SiMe 3 ) 2 only led to monosubstituted compounds (Dipp 2 Nacnac)M[E(SiMe 3 ) 2 ]Cl [E=P, M=Ga(1), In (2); E=As, M=Ga (3), In (4)], regardless of the stoichiometric ratios used. In contrast to the steric effect of the SiMe 3 groups in 1-4, the reactions of the corresponding halides with LiPH 2 ⋅DME (or KAsH 2 ) facilely yielded the dipnictogenide compounds (Dipp 2 Nacnac)M(EH 2 ) 2 (E=P, M=Al (5), Ga (6), In (7); E=As, M=Al (8), Ga (9)), avoiding the use of flammable and toxic PH 3 and AsH 3 for their synthesis. The compounds 5-9 are the first examples of monomeric Group 13 diphosphanides and diarsanides in which the metal center is bound to two terminal PH 2 and AsH 2 groups, respectively. In contrast to the successful synthesis of the indium diphosphanide (Dipp 2 Nacnac)In(PH 2 ) 2 , the reaction of (Dipp 2 Nacnac)InCl 2 with KAsH 2 led to an indium mirror due to the instability of the target product., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

We report the synthesis of a gallium complex incorporating redox-active pyridyl nitroxide ligands. The (pyNO−)2GaCl complex was prepared in 85% yield via a salt metathesis route and was characterized by 1H and 13C NMR spectroscopies, X-ray diffraction, and theory. UV–Vis absorption spectroscopy and electrochemistry were used to access the optical and electrochemical properties of the complex, respectively. Our discussion focuses primarily on a comparison of the gallium complex to the corresponding aluminum derivative and shows that although the complexes are very similar, small differences in the electronic structure of the complexes can be correlated to the identity of the metal. [ABSTRACT FROM AUTHOR]

The structure of the title compound, [Al2(OH)2(C6H12N2O)6]I4·4C6H12N2O (systematic name: di-μ2-hydroxido-bis-{tris-[1,3-di-methyl-tetra-hydro-pyrimidin-2(1H)-one-κO]aluminium} tetra-iodide 1,3-di-methyl-tetra-hydro-pyrimidin-2(1H)-one tetra-solvate), is composed of two Al(C6H12N2O)3 moieties linked into a centrosymmetric dinuclear unit by a pair of bridging hydroxide ions. The aluminium cations show a distorted trigonal bipyramidal AlO5 coordination environment formed only by monodentate ligands. The Al-O bond lengths are in the range 1.789 (2)-1.859 (2) Å (mean bond length = 1.818 Å). The non-coordinating iodide anions compensate the charge of the complex cation. The remaining solvent mol-ecules and the iodide counter-anions inter-act with the complex cation by weak non-classical C-H⋯I and C-H⋯O hydrogen bonds.