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Phosphaamidine metal complexes Rh2Cl2[Ph2PC(Ph)NPh]2μ-CO (1), RuCl2[Ph2PC(Ph)N(Ph)]2 (2), [Rh{iPr2PC(Ph)NiPr}(COD)]BF4 (3), and RuCl2[iPr2PC(Ph)NiPr](DMSO)2 (4) are prepared by combining phosphaamidines Ph2P-C(Ph)NPh and iPr2P-C(Ph)NiPr (1,3-P,N) with their corresponding metal ions. Complexes 1 and 2 are stable in air while 3 and 4 are stable under inert conditions. For further comparison of structure and stability, a Ru(II) phosphaguanidine complex, RuCl2[Me2NC(PPh2)NiPr](DMSO)2 (6) was prepared. Complex 6 is stable in air and in the presence of water. The structures of the phosphaamidine and phosphaguanidine complexes, determined using single crystal X-ray diffraction, revealed P,N bidentate coordination. While all five complexes have some activity as precatalysts, complex 6 was the most active.

Transformation of 1-t-Boc-4-methoxyindole-3-glucosinolate under acidic conditions yielded the potent phytoalexin rapalexin A, providing its first biomimetic synthesis via Lossen type rearrangement, while a novel 1-thioimidocarbonyl-β-d-glucopyranose heterocyclic system was obtained under basic conditions via Neber type rearrangement.

Dimeric rhodium N-heterocyclic carbene complexes are demonstrated to be effective catalyst precursors for directed C-H borylation reactions at room temperature. The reactions are highly selective for mono-borylation and can be combined with a one-pot Suzuki-Miyaura coupling to give C-H arylation products with exclusive selectivity for mono-arylation without the requirement for steric blocking groups.

Here we report the structure and optical properties of a new Cu–cysteamine complex (Cu–Cy) with a formula of Cu3Cl(SR)2 (R = CH2CH2NH2). This Cu–Cy has a different structure from a previous Cu–Cy complex, in which both thio and amine groups from cysteamine bond with copper ions. Single-crystal X-ray diffraction and solid-state nuclear magnetic resonance results show that the oxidation state of copper in Cu3Cl(SR)2 is +1 rather than +2. Further, Cu3Cl(SR)2 has been observed to show intense photoluminescence and X-ray excited luminescence. More interesting is that Cu3Cl(SR)2 particles can produce singlet oxygen under irradiation by light or X-ray. This indicates that Cu3Cl(SR)2 is a new photosensitizer that can be used for deep cancer treatment as X-ray can penetrate soft tissues. All these findings mean that Cu3Cl(SR)2 is a new material with potential applications for lighting, radiation detection and cancer treatment.

Redox active cyclopeptides Fc[CSA]2 (5), Fc[Gly-CSA]2 (6), Fc[Ala-CSA]2 (7), Fc[Val-CSA](2) and Fc[Leu-CSA]2 (9) (CSA = cysteamine) which are formed by the reaction of ferrocenedicarboxylic acid with peptide cystamines at high dilutions. These systems exhibit H-bonding involving the amide NH in solution as shown by their temperature dependent NMR spectra. With the exception of 5, the ferrocene macrocycles display intramolecular N...O cross-ring H-bonding in the solid state involving the amino acids proximal to the ferrocene.

Whereas a new coordinatively unsaturated Cp*Ru(kappa(2)-P,O) complex (1a) forms adducts with two-electron donors (including sigma-H(2) and mu-N(2) ligands), double Si-H bond activation is observed upon treatment with Ph(2)SiH(2) or PhSiH(3), leading to the clean formation of products corresponding to the net insertion of a Ph(2)Si: or Ph(H)Si: fragment into the Ru-O bond of 1a.

The salts X2MMMX(AF6)(A = As or Sb, M = S or Se, X = Cl or Br) were prepared quantitatively by the reaction of stoichiometric amounts of MX3AF6 and M or from stoichiometric amounts of M, X2 and AsF5(M = S or Se; X = Br) in liquid SO2. They have been characterised by elemental analysis, single-crystal X-ray diffraction, Fourier-transform (FT)-Raman and 77Se FT-NMR spectroscopy. The crystal structures of X2MMMX(AsF6) consist of (X2MMMX)+ cations and AsF6– anions. The structure of the (X2MMMX)+ cation is dominated by an intracationic halogen–chalcogen contact and M–M bond alternation giving rise to a short M–M bond distance indicative of thermodynamically stable npπ–npπ(n= 3 or 4) bonds. Since the structure of these cations is different from those of (YM)2MY+(Y = Me or C6F5), theoretical calculations were performed to understand these differences and the bonding in these cations. In the X2SSSX(AsF6) salts (X = Cl or Br) the structures of the cations are disordered and therefore exact bond distances could be not obtained. However, bond distances were estimated from their FT-Raman spectra and supported by molecular orbital calculations. The FT-Raman spectrum of Se2Br5AsF6 is reported.

Coordination complexes of (2,6-Me2C6H3S)2Pb (1) with flexible bidentate ligands have been prepared to explore new bonding environments for Pb(II) thiolates. The reaction of 1 with a series of ethylenediamine and ethylenediphosphine ligands resulted in isolation of the adducts [(2,6-Me2C6H3S)2Pb]2(tmeda) (9), [(2,6-Me2C6H3S)2Pb]3(dmpe) (10) and [(2,6-Me2C6H3S)2Pb]2(dppe) (11) [tmeda = N,N,N',N'-tetramethylethylenediamine; dmpe = bis(dimethylphosphino)ethane; dppe = bis(diphenylphosphino)ethane]. The X-ray crystal structure of 9 shows a dinuclear species in which tmeda is chelating a ψ-trigonal bipyramidal S2N2 Pb centre via axial and equatorial sites. The structure of 10 displays a trinuclear structural unit in which dmpe is chelating a ψ-trigonal bipyramidal S2P2 Pb centre via equatorial sites. Compounds 9 and 10 also contain a second unique metal centre with ψ-tetrahedral S3Pb bonding motifs. The structure of 11 shows the dppe ligand bridging two Pb ψ-tetrahedral S2P metal bonding environments. Static (207)Pb solid-state NMR (SSNMR) spectra of 9-11 and [Ph4As][(PhS)3Pb] (12) were acquired with cross polarization (CP)-CPMG and frequency swept pulse (WURST)-CPMG pulse sequences, and the efficiencies of these pulse sequences are compared. The (207)Pb SSNMR spectra reveal that the lead chemical shift anisotropies (CSA) vary greatly between the different Pb sites, and are generally large in magnitude. DFT calculations are utilized to relate the orientations of the (207)Pb nuclear magnetic shielding tensors to the molecular structures, and to aid in spectral assignment where multiple Pb centres are present. The combination of X-ray diffraction, (207)Pb SSNMR and DFT is shown to be invaluable for the structural characterization of these important structural motifs, and should find wide-ranging application to numerous lead coordination compounds.

The treatment of Me3SiN=P(NHBut)3 with three equivalents of LiBun in toluene produces (Li3(P(NBut)3(NSiMe3)))2 comprised of a Li6N6 cyclic ladder capped on the two hexagonal faces by mu 3-PNSiMe3 groups; the corresponding reaction of O=P(NHBut)3 yields the face-sharing double-cubane (Li2(THF)P(O)(NBut)2(NHBut))2 with a central Li2O2 ring.

Treatment of [Li2Te(NBut)3]2 with Sn(O3SCF3)2 or SnCl2 in diethyl ether generates the stannanetellurone [ButNSn(mu-NBut)2 TeNBut](mu3-SnTe) involving four-coordinate tin with d(Sn=Te) = 2.589(1) A; the two Sn and two Te atoms are in different oxidation states (+II/+IV and +IV/-II, respectively).

Lithiation of SP[N(H)R]3 with LiBun produces the dimers [(THF)LiSP(NR)(NHR)2]2 (R = Pri) or ([LiSP(NR)-(NHR)2][(THF)LiSP(NR)2(NHR)])2 (R = But) with central Li2N2 or Li2S2 rings, respectively; further lithiation yields the dianion [SP(NR)2(NHR)]2- (R = Pri) or leads to sulfur extrusion when R = But.

Treatment of [Cp*RuCl](4) with 1-diisopropylphosphino-2-indanone () afforded Cp*Ru(Cl)(kappa(2)-P,O-) () in 96% isolated yield. Dehydrohalogenation of under an atmosphere of N(2) provided the dinuclear complex (78% isolated yield), which is comprised of two coordinatively unsaturated Cp*Ru(kappa(2)-P,O) fragments () linked by an end-on coordinated micro-N(2) ligand. Although complex has not been observed directly, reactivity studies demonstrated that can serve as a convenient source of . Isolable adducts of were prepared via exposure of to an atmosphere of CO (93% yield, ) or two equivalents of PhCN (91% yield, ). Exposure of to an atmosphere of H(2) afforded the adduct .(sigma-H(2)) () quantitatively; the clean conversion of back into occurred upon evacuation and re-introduction of a N(2) atmosphere. Treatment of with two equivalents of PhSiH(3) or Ph(2)SiH(2) afforded products featuring (H)(2)Ru-SiPhX-O fragments ( and , respectively; both 95% isolated yield) corresponding to net double geminal Si-H bond activation of the organosilane in which the extruded silylene fragment has inserted into the Ru-O bond of the putative intermediate . Similar reactivity was observed upon treatment of with two equivalents of mesitylborane to give (82% isolated yield). While minimal Ru-HSi interactions were identified for , in solution and the solid state, the hydride ligands in were observed to bridge ruthenium and boron. Crystallographic characterization data were obtained for .0.5C(6)H(6), , , and .

The high-yield synthesis, spectroscopic and structural determination of three new uranium(IV) and thorium(IV) “ate” complexes supported by three different diamido ether ligands are reported. The reaction of Li2[2,6-iPr2PhN(CH2CH2)]2O (Li2[DIPPNCOCN]) with 1 equiv. of UCl4 in THF generates [DIPPNCOCN]UCl3Li(THF)2 (1), while reaction in toluene/ether gives salt-free [DIPPNCOCN]UCl2·½C7H8 (2), which was identified by paramagnetically shifted 1H NMR. Reaction of 0.5 equiv. of {[tBuNON]UCl2}2 ([tBuNON] = [(CH3)3CN(Si(CH3)2)]2O2−) with 3.5 equiv. LiI in toluene and a minimal amount of THF results in [tBuNON]UI3Li(THF)2 (3) and is very similar in structure to 1. {[MesNON]ThCl3Li(THF)}2 (4), a dimeric complex with a Th2Li2Cl6 core, is prepared by reaction of Li2[2,4,6-Me3PhN(Si(CH3)2)]2O (Li2[MesNON]) with ThCl4 in THF. The analogous reaction in toluene did not yield the salt-free complex but rather a sterically crowded diligated compound, [MesNON]2Th (5), which was also structurally characterized. Complex 5 was prepared rationally by reacting 2 equiv. Li2[MesNON] with ThCl4 in toluene. The reaction of 1 and 3 with 2 equiv. of LiCH2Si(CH3)3 generates the stable, salt-free organoactinides [DIPPNCOCN]U(CH2Si(CH3)3)2 (6) and [tBuNON]U(CH2Si(CH3)3)2 (7). Complex 6 was structurally characterized. These reactions illustrate the viability of “ate” complexes as useful synthetic precursors.

1,1'-bis(tert-butoxycarbonylamino)ferrocene (6), a protected derivative of 1,1'-diaminoferrocene, has been synthesized by a very convenient method and serves as a synthon for 1,1'-diaminoferrocene. Its structure in solid state and in solution has been studied by NMR and X-ray crystallography. 1,1'-bis(tert-butoxycarbonylamino)ferrocene serves as starting material for the synthesis of amino acid conjugates of L- and D-alanine. The structures of these bioconjugates have been studied by NMR and CD spectroscopy and X-ray crystallography and reveal that the chiral organization of the podant amino acid chains is controlled by the chirality of the attached amino acid. The substituents engage in strong intramolecular H-bonding generating 14-membered H-bonded rings, a motif previously unrealized in ferrocene-amino acid and peptide conjugates.

Stable dark red (M = Al) or dark green (M = Ga) neutral radicals {[PhB(mu-NtBu)2]2M} are obtained by the oxidation of their corresponding anions with iodine, and EPR spectra supported by DFT calculations show that the spin density is equally delocalized over all four nitrogen atoms in these spiroconjugated systems.

The reaction Of TeCl4 and N(SiMe3)3, followed by the addition of AsF5 gives Te4N2Cl8(AsF6)2·2SO2, shown by its X-ray crystal structure to contain Te4N2Cl82+([(Cl3Te)[graphic omitted]Te(Cl)]2+), the first tellurium–nitrogen–halogen cation.

The rapid reaction of dry SO2 gas with (SnNBut)4 in THF at 23 °C produces the dimer [(SnNBut)4μ-OSO2]2(THF) in which two imidotin cubanes are linked through one of their tin atoms by a bridging (η1, η2) sulfito ligand.

An improved synthesis of SF5(CN), by direct fluorination of SF3(CN), has been achieved. This product forms a stable adduct at low temperature with AsF5, and addition of MeCN to this adduct led to very pure SF5(CN). The SF5(CN)·AsF5 adduct has been characterized by vibrational and 19F Fourier-transform NMR spectroscopy and by its dissociation vapour-pressure curve. The salt SNSAsF6 and an excess of SF5(CN) reacted in sulfur dioxide solution to give the stable salt F5S[graphic omitted]AsF6 which has been characterized by vibrational, 19F NMR and mass spectroscopy and X-ray crystallography. The structure consists of discrete F5S[graphic omitted]+ cations and AsF6– anions. The mass spectrum of F5S[graphic omitted]AsF6 was consistent with loss of AsF5 and fluoride ion transfer to give F5S[graphic omitted] which dissociated to SF4 and F2[graphic omitted]. Reduction of a dilute solution of the salt in SO2 led to identification (ESR spectroscopy) of the radical F5S[graphic omitted]˙.