Two new bis-bidentate bridging ligands have been prepared, L (naph) and (anth), which contain two chelating pyrazolyl-pyridine units connected to an aromatic spacer (naphthalene-1,5-diyl anthracene-9,10-diyl respectively) via methylene connectors. Each of these reacts with transition metal dications having a preference for octahedral coordination geometry afford {M 8L 12} (16+) cages (for M = Cu, Zn; (naph), Co, Ni, Cd) approximately cubic arrangement ions ligand spanning each the twelve...

Zinc–salophen compounds 1–3 incorporating in the given order 1,2-diaminobenzene, 2,3-diaminonaphthalene, and 9,10-diaminophenantrene moieties were synthesised. Their binding properties toward a series of tertiary amines assessed by UV-Vis fluorescence spectroscopy chloroform solution. Unprecedented selectivities quinuclidine vs. triethylamine higher than 105 recorded, thereby revealing dramatic influence steric effects on axial coordination amines. X-Ray diffraction analyses showed that...

The new dialkyl(aryl) lithium zincates [(THF)(2)Li(C(6)H(4)-OMe)MeZnMe] (4), [(TMEDA)Li(C(6)H(4)-OMe)MeZnMe] (6), [(THF)(3)Li(C(6)H(4)-OMe)(t)BuZn(t)Bu] (7), and [(PMDETA)Li(C(6)H(4)-OMe)(t)BuZn(t)Bu] (8) have been prepared by co-complexation reactions of lithiated anisole with the relevant dialkylzinc compound Lewis base. These heterobimetallic compounds characterized in solution using (1)H, (13)C{H}, (7)Li NMR spectroscopy, molecular structures 6 8 elucidated X-ray crystallography. In...

A series of ligands LPh, Lnaph and Lanth, which contain two bidentate pyrazolyl–pyridine termini separated by an aromatic (1,2-phenyl, 2,3-naphthyl or 2,3-anthracenyl, respectively) spacer have been used to prepare tetrahedral cage complexes the form [M4L6]Xn, in a bis-bidentate bridging ligand spans each six edges M4 tetrahedron one anion is bound central cavity. Several new examples structurally characterised, including example with (Lanth), first second-row transition metal ion [Cd(II)],...

Abstract Check M(etal)ate: The chessboard and the figures represent a special reaction in which different low‐polarity metals can metalate arenes directly when they are brought into right position. In combination of queen (sodium) knight (chromium or iron), it is possible for (usually weaker piece) to make direct deadly hit on king (benzene) this game elemental chess. magnified image

The study of co-complexation reactions between NaCH(2)SiMe(3) and Mg(CH(2)SiMe(3))(2) has allowed the isolation structural elucidation first solvent-free alkali-metal alkylmagnesiate [{NaMg(CH(2)SiMe(3))(3)}(∞)] (1) as well related sodium alkyl [{(NaCH(2)SiMe(3))(4)}(∞)] (3).

Abstract [(Trimethylsilyl)methyl]sodium [NaCH 2 SiMe 3 ] ( 1 ) was prepared by a metathesis reaction of [(trimethylsilyl)methyl]lithium [LiCH with sodium tert ‐butoxide in n ‐hexane. Polydentate donors such as N , N′ ‐tetramethylethylenediamine (TMEDA) and N″ ‐pentamethyldiethylenetriamine (PMDETA) form ‐hexane‐soluble complexes the potassium congener [KCH ). The crystal structures polymers [(TMEDA)NaCH 1a [(PMDETA)KCH 2a were determined infinite helical chains exhibiting or screw‐axis...

Building on recent advances in synthesis showing that the addition of inorganic salts to Grignard reagents can greatly enhance their performance alkylation reactions ketones, this study explores EtMgCl with benzophenone presence stoichiometric or catalytic amounts ZnCl(2) aim furthering understanding role and constitution organometallic species involved these transformations. Investigations into metathesis three molar equivalents led isolation characterisation (X-ray crystallography (1)H...

This paper presents the synthesis and characterization of new homoleptic lithium magnesiate reagents incorporating silyl-substituted alkyl ligand CH2SiMe3 in presence a variety Lewis base donors, namely tetrahydrofuran (THF), 1,4-dioxane, N,N,N′,N′-tetramethylethylenediamine (TMEDA), N,N,N′,N″,N″-pentamethyldiethylenetriamine (PMDETA). The constitution these bimetallic compounds has been assessed both solid state solution using combination X-ray crystallographic studies multinuclear NMR...

Meta–meta metalation: Remarkably, toluene can be directly dimanganated or dimagnesiated at the 3,5-positions using bimetallic bases with active Me3SiCH2 ligands (see scheme, blue). In contrast, n-butyl lead to 2,5-metalation (red). tmp=2,2,6,6-tetramethylpiperidide. Organolithium reagents have long enjoyed iconic status amongst synthetic chemists, in part because of their unrivaled ability affect directed metalation (lithiation, lithium–hydrogen exchange) reactions on arenes, heteroarenes,...

Inside out approach: Twofold deprotonation of benzene by a sodium monoalkyl bisamido manganate(II) reagent derived from BuNa, 2,2,6,6-tetramethylpiperidine, and Mn(CH2SiMe3)2 has produced the first inverse-crown complex in which transition-metal atoms are incorporated host (see X-ray structure, blue N, green Na, purple Mn). Variable-temperature magnetization measurements show that is antiferromagnetic.

Abstract Extending the recently introduced concept of “alkali‐metal‐mediated manganation” to functionalised arenes, heteroleptic sodium manganate reagent [(tmeda)Na(tmp)(R)Mn(tmp)] ( 1 ; TMEDA= N , ′, ′‐tetramethylethylenediamine, TMP=2,2,6,6‐tetramethylpiperidide, R=CH 2 SiMe 3 ) has been treated with anisole or ‐diisopropylbenzamide in a 1:1 stoichiometry hexane. These reactions afforded crystalline products [(tmeda)Na(tmp)( o ‐C 6 H 4 OMe)Mn(tmp)] and [(tmeda)Na(tmp){ ‐{C(O)N( i Pr) C...

Abstract Ditopic bis(acylhydrazone) ligands, derived from the reactions of carbohydrazides with 2‐phenylpyrimidine‐4,6‐dicarbaldehyde and designed for grid formation octahedrally coordinating transition‐metal ions, exhibit a varied coordination chemistry depending upon degree their deprotonation. The neutral acylhydrazones are relatively poor ligands seemingly involved in multiple, labile complexation equilibria varying solvent particular metal salt solution; nevertheless, complexes...

While N(2) and CO have played central roles in developing models of electronic structure, their interactions with transition metals been widely investigated, the valence isoelectronic diatomic molecules EX (E = group 13 element, X 17 element) yet to be isolated under ambient conditions, either as "free" molecule or a ligand simple metal complex. As part program designed address this deficiency, together wider issues chemistry cationic systems [L(n)M(ER)](+) B, Al, Ga; R aryl, amido, halide),...

Performed with a desire to advance knowledge of the structures and mechanisms governing alkali-metal-mediated zincation, this study monitors reaction between TMP-dialkylzincate reagent [(TMEDA)Na(TMP)((t)Bu)Zn((t)Bu)] 1 trifluoromethyl benzene C(6)H(5)CF(3) 2. A complicated mixture products is observed at room temperature. X-ray crystallography has identified two these as ortho- meta-regioisomers heterotrianionic [(TMEDA)Na(TMP)(C(6)H(4)-CF(3))Zn((t)Bu)], 3-ortho 3-meta, respectively....

Numerous organic transformations rely on organozinc compounds made through salt-metathesis (exchange) reactions from organolithium or Grignard reagents with a suitable zinc precursor. By combining X-ray crystallography, NMR spectroscopy and DFT calculations, this study sheds new light the constitution of organometallic species involved in important synthetic tool. Investigations into metathesis equimolar amounts (RMgX) ZnCl(2) THF led to isolation novel magnesium-zinc hybrids,...

Expanding the synthetic potential of Mg–Zn hybrid organyl reagents (generated via transmetallation reactions), this study uncovers a versatile approach, involving sequence direct Zn–I exchange and Pd catalysed cross-coupling reactions which grants access to wide range asymmetric bis(aryls). By combining X-ray crystallography with ESI-MS non-deuterium NMR spectroscopic studies, new light is shed on heterobimetallic constitution intriguing organometallic species [(THF)4MgCl2Zn(tBu)Cl] (1)...

With the aim of introducing diisopropylamide [NiPr(2)](-) ligand to alkali-metal-mediated manganation (AMMMn) chemistry, temperature-dependent reactions a 1:1:3 mixture butylsodium, bis(trimethylsilylmethyl)manganese(II), and diisopropylamine with ferrocene in hexane/toluene have been investigated. Performed at reflux temperature, reaction affords surprising, ferrocene-free, hydrido product [Na(2)Mn(2) (mu-H)(2){N(iPr)(2)}(4)]2 toluene (1), first Mn inverse crown complex. Repeating...

Two potassium-dialkyl-TMP-zincate bases [(pmdeta)K(mu-Et)(mu-tmp)Zn(Et)] (1) (PMDETA = N,N,N',N'',N''-pentamethyldiethylenetriamine, TMP 2,2,6,6-tetramethylpiperidide), and [(pmdeta)K(mu-nBu)(mu-tmp)Zn(nBu)] (2), have been synthesized by a simple co-complexation procedure. Treatment of 1 with series substituted 4-R-pyridines (R Me(2)N, H, Et, iPr, tBu, Ph) gave 2-zincated products the general formula [{2-Zn(Et)(2)-mu-4-R-C(5)H(3)N}(2)2{K(pmdeta)}] (3-8, respectively) in isolated crystalline...

Two lithium and one sodium diamine bis(phenolate) complexes have been prepared characterised by X-ray crystallography NMR spectroscopy. parent bis(phenol) ligands were utilised in the study (1-H2 2-H2). Dimeric (1-Li2)2 was treating 1-H2 with two molar equivalents of n-butyllithium hydrocarbon solvent. It adopts a ladder-like structure solid state, which appears to deaggregate C6D6 solution. The monomeric (hence, dinuclear) TMEDA-solvated species [2-Li2·(TMEDA)] has chemically unique Li...

In a study aimed at developing the diisopropylamido (DA) chemistry of zincates, new lithium DA-zincate [(TMEDA)·Li(tBu)(DA)Zn(tBu)] (4) has been synthesized by an interlocking cocomplexation approach comprising mixing its three component chemicals, LDA, tBu2Zn, and TMEDA, in 1:1:1 ratio hexane solution. Previously made transamination from corresponding TMP-zincate, known sodium congener [(TMEDA)·Na(tBu)(DA)Zn(tBu)] (2) was also this approach, substituting NaDA for LDA. Closely resembling...