Synthesis of bimetallic[Sn,A]-μ-oxoisopropoxyacetate and -μ-oxoisopropoxide and their acetylacetone and benzoylacetone derivatives

Bimetallic [Sn^IV,Al^III-μ-oxoisopropoxyacetate (Bu₂Sn(OAc)OAl(OⁱPr)₂] and bimetallic [Sn^IV,Al^III]-μ- oxoisopropoxide [Bu₂SnO₂Al₂(OⁱPr)₄] have been synthesized by thermal condensation of dibutyltin diacetate with aluminium isopropoxide in 1:1 and 1:2 molar ratio, respectively. Reactions of these compounds with acetylacetone and benzoylacetone in these molar ratios yielded compounds of the type [Bu₂Sn(OAc)OAl(OⁱPr)L], [Bu₂Sn(OAc)OAlL₂], [Bu₂SnO₂Al₂(OⁱPr)₃L] and [Bu₂SnO ₂Al₂(OⁱPr)₂L₂] (where L = acetylacetonate or benzoylacetonate anion). The μ-oxo compounds and their derivatives have been characterized by elemental analysis and spectroscopic techniques (IR, ¹H NMR, ¹³C NMR, ²⁷Al NMR and ¹¹⁹Sn NMR).     

The chemistry of 1,3,5-triazacyclohexane complexes 5: cationic zinc(II) alkyl complexes of N-alkylated 1,3,5-triazacyclohexanes and 13-benzyl-1,5,9-triazatricyclo[7.3.1.0]-tridecane

Diethylzinc reacts with hydroperchlorates of N-alkylated 1,3,5-triazacyclohexanes (R₃TAC; R = methyl (Me), benzyl (Bz), isopropyl (ⁱPr)) and with the hydrotetrafluoroborate of 1,3,5-tris-(para-fluorobenzyl)-1,3,5-triazacyclohexane (FBz₃TAC) to give the corresponding cationic zinc ethyl complexes [(R₃TAC)Zn(Et)][X] (X = ClO₄⁻, BF₄⁻). Similar complexes were obtained from diethylzinc treated with [HNMe₂Ph][BF₄] or [HNMe₂Ph][B(C₆F₅)₄](Et₂O) in the presence of R₃TAC (R = Bz, FBz, s-1-phenylethyl (s-PhMeCH)). A product of decomposition of [(Bz₃TAC)Zn(Et)][ClO₄] was analyzed by X-ray diffraction. The structures of [({s-PhMeCH}₃TAC)Zn(Et)][BF₄] an [(FBz₃TAC)Zn(Et)][BF₄] were estimated using nuclear Overhauser enhancement spectroscopy. Protonolysis of diethylzinc with [HNMe₂Ph][BF₄] in the presence of 13-benzyl-1,5,9-triazatricyclo[7.3.1.0^5,13]-tridecane (BzTATC) yielded the complex [(BzTATC)Zn(Et)][BF₄].     

Di- and tri-organotin(IV) diphenyldithiophosphinates

Di- and tri-organotin(IV) diphenyldithiophosphinates, R₂Sn(S₂PPh₂)₂ (R = Me, n-Bu, Bz, Ph) and R₃SnS₂PPh₂ (R = Me, Cy, Bz, Ph) were prepared by reaction of the corresponding organotin chlorides or oxides with diphenyldithiophosphinic acid or its ammonium salt. All the compounds were characterized by IR and ¹H NMR spectra. For R₂Sn(S₂PPh₂)₂ (R = Me, Ph) and Ph₃SnS₂PPh₂ mass spectra and tin-119m Mössbauer spectra were also recorded. Monodentate bonding of the dithiophosphinic ligand and tetrahedral structures are proposed for the triorganotin derivatives, while in diorganotin compounds there appears to be distorted octahedral geometry around tin, with anisobidentate dithiophosphonic ligands.     

Heterobimetallic Mo---Sn complexes. Reactions of [Mo(CO)3(CH3CN)2(Cl)(SnRCl2)] (R = Me, Ph) with 4(4-XC6H4)3 (X = Cl, F, H, Me, MeO)

Three families of heterobimetallic compounds were obtained by reaction of [Mo(CO)₃(CH₃CN)₂(Cl)(SnRCl₂)] (R = Ph, Me) with P(4-XC₆H₄)₃ (X = Cl, F, H, Me, MeO). The type of compound obtained dependent on the solvent and concentration of the starting compound. So, [Mo(CO)₂(CH₃COCH₃)₂(PPh₃)(Cl)(SnRCl₂)]·nCH₃COCH₃ (R = Ph, n = 0.5; R = Me, n = 1) (type I) and [Mo(CO)₃{P(4-XC₆H₄)₃}(μ-Cl)(SnRCl₂)]₂ (R = Ph, X = Cl, F, H, Me, MeO; R = Me, X = Cl, F) (type II) were isolated from acetone solution in ca 0.05 M and 0.1 M concentrations, respectively. However, [Mo(CO)₃(CH₃CN) {P(4-XC₆H₄)₃}(Cl)(SnRCl₂)] (R = Ph, X = H; R = Me, X = Cl, F, H) (type III) were obtained from dichloromethane solution independently of the concentration used. All new complexes showed a seven-coordinate environment at molybdenum, containing Mo---Cl and Mo---Sn bonds. Mössbauer spectra indicated a four-coordination at tin for type III complexes.     

In situ generated pyroglutamate bridged polyoxotitaniums with strong circular dichroism signal

In this text, we use inexpensive and natural amino acid, successfully obtained the asymmetric crystallization of three PTCs, [Tis(O~iPr)_(14)(μ_2-O)(μ_3-O)_2(D/L-pGlu)_2](D-PTC-53; L-PTC-53; H2 pGlu=pyroglutamic acid) and [Ti_6(O~iPr)_(14)(μ_2-O)(μ_3-O)_2(D-pGlu)_2][Ti_6(O~iPr)_(14)((μ_2-O)(μ_3-O)_2(L-pGlu)_2](D,L-PTC-53). Interestingly, in situ lactamide reaction starting from glutamic acid to pyroglutamic acid was observed. In addition,the chirality features of these PTCs have been thoroughly discussed.The two enantiomers crys tallize in chiral P21 space group.The optically pure pGlu ligands transform its chirality to the inorganic titanium oxo clusters. As a result, the stack of these inorganic clusters generates homochiral helical chains along the characteristic axial direction.Apart from the microscopic structural analysis, the macroscopic solid-state samples exhibit unusual strong circular dichroism(CD) signals,further verified the homochiral feature of the enantiomers.     

Binuclear methyplatinum and phenylplatinum complexes with bis(dimethylphosphino)methane ligands

Reaction of cis-[Ptph₂(SMe₂)₂] with Me₂PCH₂PMe₂ (dmpm) gave cis-[PtPh₂(dmpm-P)₂] (1) or cis,cis-[Pt₂Ph₄(μ-dmpm)₂] (2) and reaction of 1 with [Pt₂Me₄(μ-SMe₂)₂] gave cis,cis-[Ph₂Pt(μ-dmpm)₂PtMe₂] (3). Reaction of 1 with trans-[PtClR(SMe₂)₂] gave cis,trans-[Ph₂Pt(μ-dmpm)₂PtClR], R = Me (5) or Ph (6), and in polar solvents, these isomerized to give [Ph₂Pt(μ-dmpm)₂PtR]⁺Cl⁻. When R = Me, further isomerization via the phenyl group transfer gave [PhMePt(μ-dmpm)₂PtPh]⁺Cl⁻. Oxidative addition of methyl iodide occurred reversibly at the cis-[PtMe₂P₂ unit of 3 to give cis,fac-[Ph₂Pt(μ-dmpm)₂PtIMe₃] but complex 2 failed to react with MeI. A comparison with similar known complexes of Ph₂PCH₂PPh₂ (dppm) is made and differences are attributed primarily to the lower steric hindrance of dmpm.     

Syntheses and crystal structures of lithium derivatives of diphosphanes R2P–P(SiMe3)Li · 3L, R = Ph, Pr and Pr2N, L = THF or DME

The reactions of R₂P–P(SiMe₃)₂ (R = Ph, ⁱPr and ⁱPr₂N) with BuLi in THF or DME solution lead to ion-contacted lithium derivatives R₂P–P(SiMe₃)Li · 3THF (R = ⁱPr, ⁱPr₂N) with tetrahedrally surrounded Li atoms and to the solvent-separated ionic [Li · 3DME]⁺[Ph₂P–PSiMe₃]⁻ with an octahedrally surrounded Li atom as confirmed by X-ray crystal structure analysis. The reaction of BuLi with Ph₂P–P(SiMe₃)₂ is accompanied with a significant side-reaction leading to Ph₂P–PPh₂ and to LiP(SiMe₃)₂.     

The lively chemistry of the di-μ-methylene-bis(pentamethylcyclopentadienyl-rhodium) complexes, analogues of surface reactions in heterogeneous catalysis

The chemistry of the di-μ-methylene-bis(pentamethylcyclopentadienyl-rhodium) complexes is reviewed. The complex [{(η⁵-C₅Me₅)RhCl₂}₂] (1a) reacted with MeLi to give, after oxidative work-up, blood-red cis-[{(η⁵-C₅Me₅)Rh(μ-CH₂)}₂(Me)₂], 2. This has the two rhodiums in the +4 oxidation state (d⁵), and linked by a metal-metal bond (2.620 Å). Trans-2 was formed on isomerisation of cis-2 in the presence of Lewis acids, or by direct reaction of 1a with Al₂Me₆, followed by dehydrogenation with acetone. The Rh-methyls in [{(η⁵-C₅Me₅)Rh(μ-CH₂)}₂(Me)₂] were readily replaced under acidic conditions (HX) to give [{(η⁵-C₅Me₅)Rh(μ-CH₂)}₂(X)₂] (X = Cl, Br or I); these latter complexes reacted with a variety of RMgX to give [{(η⁵-C₅Me₅)Rh(μ-CH₂)}₂(R)₂] (R = alkyl, Ph, vinyl, etc.). Trans-2 also reacted with HBF₄ in the presence of L to give first [{(η⁵-C₅Me₅)Rh(μ-CH₂)}₂(Me)(L)]⁺ and then [{(η⁵-C₅Me₅)Rh(μ-CH₂)}₂(L)₂]²⁺ (L = MeCN, CO, etc.). The {(η⁵-C₅Me₅)Rh(μ-CH₂)}₂ core is rather kinetically inert and also forms a variety of complexes with oxy-ligands, both cis-, e.g. [{(η⁵-C₅Me₅)Rh(μ-CH₂)}₂(μ-OAc)]⁺ and trans-, such as [(η⁵-C₅Me₅)Rh(μ-CH₂)}₂(H₂O)₂]²⁺. The complexes [{(η⁵-C₅Me₅)Rh(μ-CH₂)}₂(R)L]⁺ (R = Me or aryl) in the presence of CO, or [{(η⁵-C₄Me₅)Rh(μ-CH₂)}₂(R)₂] (R = Me, Ph or CO₂Me) in the presence of mild oxidants, readily yield the C---C---C coupled products RCH=CH₂. The mechanisms of these couplings have been elucidated by detailed labelling studies: they are more complex than expected, but allow direct analogies to be drawn to C---C couplints that occur during Fischer-Tropsch reactions on rhodium surfaces.     

Oxidation of organometallic complexes by water: Synthesis of diorgano(hydroxo)platinum(IV) complexes and the structure of a diorgano(aqua)platinum(IV) complex of tris(pyridin-2-yl)methanol, [PtPh2{(py)3COH---N,N′,N″}(OH2)][NO3)2 · H2O

The diorganoplatinum(II) complexes PtR₂{(py)₃COH} (R = Me, Ph; (py)₃COH = tris(pyridin-2-yl)methanol) react with water in organic solvents to form diorgano(hydroxo)platinum(IV) cations [Pt(OH)R₂{(py)₃COH}]⁺, and the cation with R = Ph reacts with dilute nitric acid to form [PtPh₂{(py)₃COH}(OH₂)]²⁺. The cation in [PtPh₂{(py)₃COH}(OH₂)][NO₃]₂ · H₂O has octahedral geometry with a Pt---O bond distance of 2.04(1) Å. The higher trans influence of phenyl than aqua ligands is reflected in the Pt---N bond distances: 2.14(2) and 2.17(1) Å trans to the phenyl groups, and 1.99(2) Å trans to the aqua ligand.     

Recent studies on metal and metalloid bis(trimethylsilyl)methyls and the transformation of the bis(trimethylsilyl)methyl into the azaallyl and β-diketinimato ligands

Recent results (post-1990) on the synthesis and structures of bis(trimethylsilyl)methyls M(CHR₂)_m (R = SiMe₃) of metals and metalloids M are described, including those of the crystalline lipophilic [Na(μ-CHR₂)]_∞, [Rb(μ-CHR₂)(PMDETA)]₂, K₄(CHR₂)₄(PMDETA)₂, [Mg(CHR₂)(μ-CHR₂)]_∞, P(CHR₂)₂ (gaseous) and P₂(CHR₂)₄, [Yb(CHR₂)₂(OEt₂)₂] and [{Yb(CR₃)(μ-OEt)(OEt₂)}₂]; earlier information on other M(CHR₂)_m complexes and some of their adducts is tabulated. Treatment of M(CHR₂) (M = Li or K) with four different nitriles gave the X-ray-characterized azaallyls or β-diketinimates , and (LL′ = N(R)C(^tBu)CHR, L′L′ = N(R)C(Ph)C(H)C(Ph)NR, LL″ = N(R)C(Ph)NC(H)C(Ph)CHR, R = SiMe₃ and Ar = C₆H₃Me₂-2,5). The two lithium reagents were convenient sources of other metal azaallyls or β-diketinimates, including those of K, Co(II), Zr(IV), Sn(IV), Yb(II), Hf(IV) and U(VI)/U(III). Complexes having one or more of the bulky ligands [LL′]⁻, [L′L′]⁻, [LL]⁻, [LL″]⁻, [L″L]⁻, [LL]⁻ and [{N(R)C(^tBu)CH}₂C₆H₄-2]²⁻ are described and characterized (LL = N(H)C(Ph)C(H)C(Ph)NH, L″L = N(R)C(^tBu)C(H)C(Ph)NR, LL = N(R)C(^tBu)CHPh). Among the features of interest are (i) the contrasting tetrahedral or square-planar geometry for and , respectively, and (ii) olefin-polymerization catalytic activity of some of the zirconium(IV) chlorides.     

Electrochemical reduction of the dithiophosphate complexes CpFe(CO)2[η-SP(S)(OR)2], (Cp = η-C5H5 or η-C5Me5)

The reductive electrochemistry of compounds of the type CpFe(CO)₂L (Cp = η-C₅H₅, η-C₅Me₅; L = SP(S)(OEt)₂, SP(S)(OⁱPr)₂) has been examined by polarography, cylic voltammetry and coulometry. The first one-electron reduction step leads to a bond rupture process with formation of a mercury compound, [CpFe(CO)₂]₂Hg, at a mercury electrode and the corresponding dimer species at a platinum electrode. The second reduction step corresponds to the reduction of the dimer [CpFe(CO)₂]₂, except in the polarographic reduction of pentamethylcyclopentadienyl compounds.     

Conversion of rhenium alkylidyne complexes that contain unsupported metal-metal double bonds into relatives that contain μ-alkylidyne ligands

Photolysis of compounds of the type [Re(CCMe₂R)(OR′)₂] (R = Me or Ph; OR′ = O′Bu, OCMe₂(CF₃), or OCMe(CF₃)₂) in benzene with a medium pressure mercury lamp yields compounds of the type [Re(OR′)₂]₂(μ-CCMe₂R)₂ in an intramolecular and irreversible manner. [Re(CCMe₂R)(OR′)₂]₂ and [Re(OR′)₂]₂(μ-CCMe₂R)₂ (OR′ = O′Bu or OCMe₂(CF₃)₂) both react with excess carbon monoxide in several solvents to afford the dimers [Re(OR′)₂(CO)]₂(μ-CCMe₂R)₂ quantitatively. An X-ray study of [Re(O^tBu)₂(CO)]₂ (μ-C^tBu)₂ shows it to consist of two distorted trigonal bipyramids connected by two symmetrically bridging neopentylidyne ligands. The unbridged dimers of general formula [Re(CCMe₂R)(OR′)₂]₂ do not react readily with simple substrates such as phosphines, olefins, or acetylenes, although [Re(CCMe₂R)(O^tBu)₂]₂ can be oxidized by iodine to yield Re(CCMe₂R)(O^tBu)₂I₂ in good yield. In contrast, {Re[OCMe(CF₃)₂]₂}₂(μ-C^tBu)₂ reacts with one equivalent of phenylacetylene to give a species in which one of the two bridging alkylidyne ligands is retained.     

Reactivity studies of [Pd2(μ-X)2(PBu3)2] (X = Br, I) with CNR (R = 2,6-dimethylphenyl), H2 and alkynes

Improved syntheses for the dimeric compounds [Pd₂(μ-X)₂(PBu^t₃)₂] (X = Br, I) have been developed and the X-ray crystal structure for the dimer with X = 1 is reported. The reactions of these dimers with CNR (R = 2,6-dimethylphenyl), H₂ and a series of terminal and substituted alkynes are also reported. The dimer with X = Br is an initiator for the catalytic polymerisation of phenylacetylene. The product of the dimers with disubstituted alkynes results in the synthesis of trimeric species with formula [Pd₃(μ-X){ν²-C₄(CO₂R)₄}₂][PBu^t₃)Me]₂ (X = Br, I; R = Me, Et). The X-ray crystal structure of one of these compounds (when R = Et and X = I) is presented, demonstrating that the palladium dimers assist the C---C coupling of the alkynes.     

Synthesis of polysilanes bearing pendant carbosilyl groups and Si-NMR probe on the tacticity using side chain silicon atoms

New functional polysilanes [R₂R¹Si(CH₂)₂SiH]_n (R=Me, R¹=H (1); R=R¹=Et (2); R=Me, R¹=Ph (3)) bearing carbosilyl side chains have been synthesized by catalytic dehydropolymerization of precursor carbosilanes R₂R¹SiCH₂CH₂SiH₃ using Cp₂TiCl₂–BuLi as a catalyst. These polymers are characterized by ¹H, ¹³C, ²⁹Si, {¹H–²⁹Si} HSQC NMR spectroscopy, GPC and TGA. Attempts to delineate the tacticity from the analysis of deconvoluted ²⁹Si{¹H}-NMR signals associated with the side chain silicon atoms reveal that the triad concentration ratio follows a Bernoullian statistical model for polymers 1 and 2 only.     

Solid-state static Cu and P CP/MAS NMR, and liquid-state EXAFS studies on copper(I) O,O′-dialkyldithiophosphate cluster compounds: Formation of the copper(I) O,O′-di-iso-amyldithiophosphate cluster compound on the surface of synthetic chalcocite

Polycrystalline octa-nuclear copper(I) O,O′-di-i-propyl- and O,O′-di-i-amyldithiophosphate cluster compounds, {Cu₈[S₂P(OR)₂]₆(μ₈-S)} where R = ⁱPr and ⁱAm, were synthesized and characterized by ³¹P CP/MAS NMR at 8.46 T and static ⁶⁵Cu NMR at multiple magnetic field strengths (7.05, 9.4 and 14.1 T). The symmetries of the electronic environments around the P sites were estimated from the ³¹P chemical shift anisotropy (CSA) parameters, δ_aniso and η. Analyses of the ⁶⁵Cu chemical shift and quadrupolar splitting parameters for these compounds are presented with the data being compared to those for the analogous octa-nuclear cluster compounds with R = ⁿBu and ⁱBu. The ⁶⁵Cu transverse relaxation for the copper sites in {Cu₈[S₂P(OⁱPr)₂]₆(μ₈-S)} and {Cu₈[S₂P(OⁱAm)₂]₆(μ₈-S)} was found to be very different, with a relaxation time, T₂, of 590 μs (Gaussian) and 90 μs (exponential), respectively. The structures of {Cu₄[S₂P(OⁱPr)₂]₄} and {Cu₈[S₂P(OⁱPr)₂]₆(μ₈-S)} cluster compounds in the liquid- and the solid-state were studied by Cu K-edge EXAFS. The disulfide, [S₂P(OⁱAm)₂]₂, was obtained and characterized by ³¹P{¹H} NMR. The interactions of the disulfide and of the potassium O,O′-di-i-amyldithiophosphate salt with the surfaces of synthetic chalcocite (Cu₂S) were probed using solid-state ³¹P NMR spectroscopy and only the presence of copper(I) dithiophosphate species with the {Cu₈[S₂P(OⁱAm)₂]₆(μ₈-S)} structure was observed.     

Preparation, spectroscopic properties and thermal stabilities of organomercury compounds containing the bulky ligand (Me3Si)3C or (PhMe2Si)3C

Mercury compounds of the types HgR¹R (R¹ = C(SiMe₃)₃; R = Me, ⁱPr, Bu, ^tBu or Ph) and HgR²R(R² = C(SiMe₂Ph)₃; R = Me, Bu, CH₂Ph or Ph) have been prepared. Those containing R¹ were made by reactions of the bromides HgR¹Br with the Grignard reagents MgRX, and those containing R² by reaction of HgR²Cl with LiR or, for R = CH₂Ph, with Mg(CH₂Ph)Cl. Replacement of one R group in HgR₂ by the bulky R¹ or R² group leads to a large increase in thermal stability, a marked shift in the ¹⁹⁹Hg resonance to lower frequency and an increase in the coupling constant ¹J(¹³C---¹⁹⁹Hg) for the Hg---R bond. The compound HgR²Cl does not react further with LiR² in tetrahydrofuran, but with LiR¹ gives HgR¹R²; the arrangement of the SiMe₂Ph groups in the latter in solution in CH₂C12 at low temperature appears to be different from that in the solid.     

稀土-钛氧簇合物EuTi6，EuTi7和La2Ti14的可控合成

As opposed to nanoparticles, atomically precise metal clusters possess a well-defined surface and crystal structure, which aids in understanding the relationship between the structure and chemical reactivity at the atomic level. As an interesting subgroup of metal cluster compounds, heterometallic lanthanide-titanium oxo clusters (LnTOCs) have attracted extensive attention due to their interesting chemical properties. However, the controlled precise synthesis of LnTOCs remains a great challenge because of the intense hydrolysis of Ti⁴⁺ ions and the competitive coordination of Ln³⁺ ions. Owing to this synthetic difficulty, high-nuclearity LnTOCs are very rare, which obstructs further studies on their properties. Choosing the appropriate chelating ligands should be an effective strategy to synthesize LnTOCs because chelating ligands can reduce the degree of hydrolysis of Ti⁴⁺ ions. Herein, four new LnTOCs, formulated as [EuTi₆(μ₃-O)₃(OC₂H₅)₈(dtbsa)₆(Hdtbsa)]·(C₂H₅OH) (1), [EuTi₇(μ₃-O)₃(μ₂-OH)₂(OⁱPr)₉(dtbsa)₆(Hdtbsa)Cl]·(HOⁱPr)₃ (2), [EuTi₇(μ₃-O)₃(μ₂-OH)₂(OⁱPr)₈(dtbsa)₇(Hdtbsa)]·(HOⁱPr)₃ (3), and [LaTi₇(μ₃-O)₃(μ₂-OH)₂(OC₂H₅)₈(dtbsa)₇(Hdtbsa)]₂·(C₂H₅OH)₄ (4), were prepared by a solvothermal method via the reaction of 3, 5-di-tert-butylsalicylic acid (H₂dtbsa), rare-earth salts, and Ti(OⁱPr)₄. Single-crystal analysis showed that the heptanuclear compound 1 contains a EuTi₆ metal core featuring a trigonal prismatic structure, wherein Eu³⁺ is located at the center of the prism formed by six Ti⁴⁺ ions. The metal core structure of octanuclear compounds 2 and 3 can be viewed as the EuTi₆ unit in 1 connected to another Ti⁴⁺ on one side of the triangular prism. The metal framework of Ln₂Ti₁₄ in 4 can be regarded as a dimer of EuTi₇ in 2. UV-Vis diffuse reflectance spectra revealed that the band gaps of 1, 2, and 3 (2.35, 2.07, and 2.16 eV, respectively) are significantly smaller than that of anatase (3.2 eV). The results of photoelectric tests indicated that the three clusters show an obvious photoelectric response, and the charge separation efficiency of 1 and 2 was better than that of 3. In order to explore the applications of these compounds to photocatalysis, H₂ production by light-driven water splitting under irradiation by a 300 W Xe lamp (300–800 nm) in an aqueous methanol solution (20 mL, 10%) was attempted. The H₂ production rates for 1, 2, and 3 were 112, 106, and 87 μmol∙h^-1∙g^-1, respectively, which were higher than that obtained with the commercial P25. Powder X-ray diffraction (PXRD) spectra and thermogravimetry (TGA) profiles confirmed the optical and thermal stability of the three clusters. This work not only provides a chelating ligand strategy for the synthesis of LnTOCs but also reveals their light-driven photocatalytic activity stemming from the small band-gap.     

Reactions of the sterically hindered organosilicon diol (Me3Si)2C(SiMe2OH)2 and some of its derivatives

The diol R₂C(SiMe₂OH)₂ (R = Me₃Si) has been shown to react with: SO₂Cl₂ to give R₂ Me₂; SOCl₂ to give R₂C(SiMe₂Cl)₂; Me₃SiI or Me₃SiCl to give R₂C(SiMe₂OSiMe₃)₂; R′COCl; (R′ = Me or CF₃) to give R₂C(SiMe₂O₂CR′)-(SiMe₂Cl); (R′CO)₂O (R′ = Me or CF₃ to give R₂C(SiMe₂O₂CR′)₂; with MeOH containing acid to give R₂C(SiMe₂OMe)₂; with neutral MeOH to give R₂C-(SiMe₂OMe)₂ and probably R₂ Me₂; MeLi to give R₂C(SiMe₂OLi)₂ (and the latter to react with PhMeSiF₂ to give R₂ Me₂). The diacetate R₂C(SiMe₂O₂CMe)₂ reacts with CsF in MeCN to give R₂C(SiMe₂F)₂; it does not react with NaN₃ or KSCN in MeCN, but the bis(trifluoroacetate) reacts with these salts with KOCN to give R₂C(SiMe₂X)₂ (X = N₃, NCS, NCO).     

Synthesis and reactions of H3Ru3(μ3-CSet)(CO)9. Reductive elimination of C---H bonds and insertion of alkynes into Ru---C and Ru---H bonds

Synthesis of H₃Ru₃(μ₃-CSEt)(CO)₉, is accomplished by base-promoted attack of ethanethiol on H₃Ru₃(μ₃-CBr)(CO)₉. Thermolysis of this product under CO yields HRu₃(CH₂SEt)(CO)₉. Reactions of H₃Ru₃(μ₃-CSEt)(CO)₉ with alkynes C₂R₂ form HRu₃(μ₃-η³-EtSCCRCR)(CO)₉ (R = Me or Ph) and Ru₃ (cis-CR=CHR)(CSEt)(CO)₉ (R = Me). The chemistry of H₃Ru₃(μ₃-CSEt)(CO)₉ differs significantly from that of the analogous ether derivative H₃Ru₃(μ₃-COMe)(CO)₉.     

New optically active organotin compounds for heterogeneous bimetallic catalysis

Chiral tin(IV) derivatives with two or three chiral centers adjacent to the metal (−)-Ment₂SnMe₂, (−)-Ment₂SnPh₂, (−)-Ment₃ SnCl, (−)-Ment₃SnH; (−)-Ment = (1R, 2S, 5R)-1-chloro-5-methyl-2-isopropylcyclohexane, R₂Sn[CH(Me)(n-Hex)]₂ (R = Bu or Ph) have been prepared either by the coupling of methylmagnesium chloride with tin halides or by the reaction of lithium stannates with optically active (2-octyl)tosylate. The stereospecificity of both processes was remarkably high, leading to new optically pure organotin reagents which have been fully characterized.