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The amino-functionalised xanthate NaS2COC2H4 N(Me)C2H4NMe2 (1) was synthesised, and its structure was determined to be a coordination polymer incorporating a six-coordinate metal with S3N2O ligation and in which the ligand delivers κ2-S,S chelate, κ2-S,O chelate, κ2-N,N chelate, and μ2-S bridging modes. 1 has been used to prepare the copper complex (Ph3P)2CuS2COC2H4N(Me)C2H4NMe2 (5), although reactions with various Zn(II) and Cd(II) salts yielded only the metal sulphide decomposition product and the free acid as its 1,1,4-trimethylpiperazinium salt (2). Attempts to insert CS2 into the alkoxides RMOC2H4N(Me)C2H4NMe2 (M=Zn, R=Et [3]; M=Cd, R=Me [4]) also failed to give the desired group 12 derivative of the amino-functionalised xanthate. The structures of 2–5 are also reported.

ZnCl2·2H2NN(H)But·H2O contains a tetrahedral metal centre with two coordinated hydrazine ligands. Hydrogen bonds between the hydrazine and water, along with weaker intermolecular NH…Cl, OH…Cl and NH…O hydrogen bonds, generate an associated lattice.

The first structures of strontium xanthates Sr(S2COR)2(ROH)3·xROH [x=0, R=Et (1), iPr (2); x=1, R=tBu (3)] have been determined. All three species adopt an approximately pentagonal bipyramidal SrS4O3 coordination sphere about the metal, although the lattice structures differ across the series and are determined by the hydrogen bonding network afforded via the alcohol moieties.

The novel bimetallic adducts [(Ph3P)2CuCl]2.ZnCl2 (1), {[(Me3P)CuCl]2.ZnCl2}n (2), [(Me3P)4Cu]+[(Me3P)2Cu(Cl)2ZnCl2]- (3), (Ph3P)2CuCl.SnCl2 (4), (Me3P)3CuSnCl3 (5), [(Ph3P)2CuCl.SbCl3]2 (6) and (Ph3P)3CuCl.SbCl3 (7) have been synthesized from combinations of R3P, CuCl and one of ZnCl2, SnCl2 or SbCl3, and their structures were determined. [(Me3P)2Cu]+[HPMe3]2+[Sb2Cl9]3- (8) and [(Me3P)4Cu]+[(Me3P)2Sb2Cl7]- (9) have been isolated as minor by-products from the reaction of Me3P, CuCl and SbCl3, and their structures were also determined.

Two new benzene tricarboxylato derivatives [(Cy2NH2)]3[C6H3(CO2)3]·4H2O (1) and [i-Bu2NH2][(Me3SnO2C)2 C6H3CO2] (2) have been synthesized and characterized by X-ray crystallography. In the solid state, compound 1 shows a three-dimensional structure involving intra- and intermolecular hydrogen bonds, whereas the X-ray structure of 2 consists of pentacoordinated Sn centers bonded to three methyl groups and two O atoms in a trans-O2SnC3 environment, bridged by oxyanions leading to a layered structure; the cation is involved in intramolecular hydrogen bonds.

Heterobimetallic thiolate [Cu(PPh3)]4(ZnCl)2 (SEt)6 has been synthesised and characterised by X-ray crystallography as a THF solvate. It contains the first structurally characterised example of a CuI-S(R)-ZnII linkage and only the second species type to embody the CuI-S-ZnII triad.

Four new phenylphosphonato SnR3 (R=Ph, Me) derivatives have been synthesized and characterized by infrared and Mössbauer spectroscopy. The structure of catena-poly[PhPO3HSnMe3]n has been determined by single-crystal X-ray diffraction analysis. The SnIV atoms are five-coordinated in all compounds, with the SnC3O2 framework in a trans trigonal bipyramidal arrangement and the PhPO3H- anions being in axial positions. The molecular structure of [PhPO3HSnMe3]n is arranged as a one-dimensional coordination polymer in which planar SnMe3 groups are axially bridged by -O-P-O- linkages of the PhPO3H- ligand. Neighboring chains are linked via O-H∙∙∙O hydrogen bond interactions, generating a layered structure. In the R2NH2(PhPO3H)2SnR′3 (R=Cy, Bu; R′=Ph, Me), the SnPh3 or SnMe3 residue is axially coordinated by two monodentate PhPO3H-. The role of the dialkylammonium cation, R2NH2+, is crucial in the lattice building via a hydrogen bond network. These hydrogen bonds contribute to the crystal stability and compactness and result in a three-dimensional arrangement. The aqua complex PhPO3(SnPh3)2·2H2O has a discrete structure and the anion PhPO32- behaves as a bidentate ligand.

The title compounds [R2NH2][C2O4SnMe3](R=i-Bu, Cy), in which tin atoms adopt a distorted trigonal bipyramidal configuration, have been prepared and submitted to an X-ray diffraction study. These compounds have been obtained from the reaction of (Cy2NH2)2C2O4·H2O or (i-Bu2NH2)2C2O4 with SnMe3Cl. In both [R2NH2][C2O4SnMe3] compounds, the trans complex has an almost regular trigonal bipyramidal geometry around the tin atom. The SnMe3 residues are connected as a chain with bridging oxalate anions in a trans-SnC3O2 framework, the oxygen atoms being in axial positions. The cations connect linear adjacent chains through NH…O hydrogen bonds giving layered structures.

The molecular structure of the amino-functionalized bismuth alkoxide, Bi[OC(CH2 NMe2)3]3 has been determined and embodies a six-coordinate bismuth atom with a fac, fac-BiO3 N3 coordination sphere.

The crystal and molecular structure of [Cy2NH2]2[C6H3(CO2)3SnMe3·H2O]·CH3CH2OH (1) has been determined by single crystal X-ray diffraction analysis. In this compound, the tin atom is pentacoordinated by three methyl groups, one oxygen atom of a water molecule and one oxygen atom deriving from the tris-carboxylato ligand, in a trans-coordinated O2SnC3 environment. The dicyclohexylammonium cations are involved in intermolecular hydrogen bonds with the non-coordinated oxygen atoms of the carboxylate, while, along with hydrogen bonds involving water and ethanol, gives rise to a complex 3D lattice structure.

When H2SeO3 is allowed to react with SnMe2Cl2 in EtOH at a 1:2 ratio colorless crystals of HSeO3SnMe2Cl are obtained which have been characterized by X-ray crystallography. The compound crystallizes in triclinic space group P1 with cell parameters a=6.9693(5) Å, b=7.5096(4) Å, c=7.5222(5) Å, α=71.503(4)°, β=75.826(3)°, γ=87.114(4)°, Z=2, V=361.82(4) Å3. The structure consists of [Me3SnO3SeH]n chains in which Me3Sn units are bridged by the selenite ligand; chains are further linked into sheets by O—H----Cl bonds. The key role of hydrogen bonds is worth emphasizing.

The structure of C2O4(SnPh3)2. 2dimethylformamide (DMF) has been determined by X-ray. It consists of monomers containing SnPh3residue trans coordinated by DMF, with the environment around the tin centre being trigonal bipyramidal.

The electronic properties of a charge-transfer (donor-acceptor) semiconducting organic co-crystal, Perylene:F4-TCNQ (PE:F4) (the donor, D, is PE and the acceptor, A, is 2,3,5,6-tetrafluoro-7,7,8,8 tetracyanoquinodimethane (F4)) in its 3 : 2 stoichiometry, are experimentally and theoretically studied. This is performed by means of electron paramagnetic resonance (EPR) and solid state electrochemical techniques, such as cyclic voltammetry (CV) measurements on single crystals. In particular, solid state electrochemistry proves to be an effective tool to probe, on a macroscopic scale, the electronic characteristics of the co-crystal. However, EPR highlights the presence of spin ½ radicals localized on F4 molecules, possibly linked to defects. The experimental findings are discussed on the basis of density functional theory (DFT) based calculations, carried out using both the projector augmented wave (PAW), with "periodic boundary conditions" (pbc), method and the localized orbitals, molecular cluster, approach. In particular, a satisfying agreement is found between the experimental, 0.336 eV (electrochemical), and theoretical, 0.303 eV (PAW), band gaps. Differences with the reported optical bandgap are discussed considering excitonic effects.

Catalytic, intermolecular hydroaminoalkylation (HAA) of styrenes provides a powerful disconnection for pharmacologically relevant γ-arylamines, but current methods cannot utilize unprotected primary alkylamines as feedstocks. Metal-catalyzed HAA protocols are also highly sensitive to α-substitution on the amine partner, and no catalytic solutions exist for α-tertiary γ-arylamine synthesis via this approach. We report a solution to these problems using organophotoredox catalysis, enabling a direct, modular, and sustainable preparation of α-(di)substituted γ-arylamines, including challenging electron-neutral and moderately electron-rich aryl groups. A broad range of functionalities are tolerated, and the reactions can be run on multigram scale in continuous flow. The method is applied to a concise, protecting-group-free synthesis of the blockbuster drug Fingolimod, as well as a phosphonate mimic of its in vivo active form (by iterative α-C-H functionalization of ethanolamine). The reaction can also be sequenced with an intramolecular N -arylation to provide a general and modular access to valuable (spirocyclic) 1,2,3,4-tetrahydroquinolines and 1,2,3,4-tetrahydronaphthyridines. Mechanistic and kinetic studies support an irreversible hydrogen atom transfer activation of the alkylamine by the azidyl radical and some contribution from a radical chain. The reaction is photon-limited and exhibits a zero-order dependence on amine, azide, and photocatalyst, with a first-order dependence on styrene.

Over the past decade, porphyrin derivatives have emerged as invaluable synthetic building blocks and theranostic kits for the delivery of cellular fluorescence imaging and photodynamic therapy. Tetraphenylporphyrin (TPP), its metal complexes, and related derivatives have been investigated for their use as dyes in histology and as components of multimodal imaging probes. The photophysical properties of porphyrin-metal complexes featuring radiometals have been a focus of our attention for the realization of fluorescence imaging probes coupled with radioimaging capabilities and therapeutic potential having "true" theranostic promise. We report hereby on the synthesis, radiochemistry, structural investigations, and preliminary in vitro and in vivo uptake studies on a range of functionalized porphyrin-based derivatives. In pursuit of developing new porphyrin-based probes for multimodality imaging applications, we report new functionalized neutral, polycationic, and polyanionic porphyrins incorporating nitroimidazole and sulfonamide moieties, which were used as targeting groups to improve the notoriously poor pharmacokinetics of porphyrin tags. The resulting functional metalloporphyrin species were stable under serum challenges and the nitroimidazole and sulfonamide derivatives remained fluorescent, allowing in vitro confocal studies and visualization of the lysosomal uptake in a gallium(III) sulfonamide derivative. The molecular structures of selected porphyrin derivatives were determined by single crystal X-ray diffraction using synchrotron radiation. We also investigated the nature of the emission/excitation behavior of model functional porphyrins using in silico approaches such as TD DFT in simple solvation models. The conjugation of porphyrins with the [7-13] and [7-14] fragments of bombesin was also achieved, to provide targeting of the gastrin releasing peptide receptor (GRPR). Depending on the metal, probe conjugates of relevance for single photon emission computed tomography (SPECT) or positron emission tomography (PET) probes have been designed and tested hereby, using TPP and related functional free base porphyrins as the bifunctional chelator synthetic scaffold and 111 In[In] or 68 Ga[Ga], respectively, as the central metal ions. Interestingly, for simple porphyrin conjugates good radiochemical incorporation was obtained for both radiometals, but the presence of peptides significantly diminished the radio-incorporation yields. Although the gallium-68 radiochemistry of the bombesin conjugates did not show radiochemical incorporation suitable for in vivo studies, likely because the presence of the peptide changed the behavior of the TPP-NH 2 synthon taken alone, the optical imaging assays indicated that the conjugated peptide tags do mediate uptake of the porphyrin units into cells.

Traditionally, fluorescence probes have focused on the detection of a single biomarker for a specific process. In this work, we set out to develop a number of fluorescence probes that enable the detection of a chosen analyte in the presence of reactive oxygen/nitrogen species (ROS/RNS). These fluorescence probes when activated result in the formation of the highly fluorescent pink dye, resorufin. Therefore, we have labelled these fluorescent probes as 'Pinkments'. Our first 'Pinkment' was shown to detect biologically relevant concentrations of ONOO- and have an excellent selectivity against other ROS/RNS. Pinkment-OH was developed to provide a core unit which could be easily functionalised to produce a range of 'AND' based fluorescence probes for the detection of ROS/RNS and a second analyte. For proof of concept, we synthesised Pinkment-OTBS and Pinkment-OAc. These 'AND'-based probes were successfully shown to detect ROS/RNS and F- or esterase, respectively.

A series of monometallic and bimetallic Al(iii) complexes with substituted naphthyl based Schiff base ligands have been prepared and characterised. When 1-aminonaphthalene based ligands were reacted with AlMe3 monometallic complexes were isolated, however, with 1,5 and 1,8-diaminonaphthalene based ligands bimetallic complexes were formed. In all cases 4-coordinate tetrahedral Al(iii) centres were observed in the solid state and in solution. There was little difference in rate of polymerisation of rac-lactide between the monometallic and bimetallic complexes based on 1,5-diaminonaphthalene. However, for the 1,8-diaminonaphthalene the complex was an order of magnitude faster than the monometallic and the analogous 1,5-system. Moreover, this complex was active at room temperature, which is rare for aluminium initiators, and PLA with a high degree (Pm = 0.82) of isotacticity was observed.

The asymmetric unit of the binuclear title compound, [Sn(2)(C(2)O(4))(C(6)H(5))(6)(CH(4)N(2)S)(2)], consists of one half of the organotin(IV) mol-ecule. The remainder is generated by a twofold rotation axis passing through the mid-point of the oxalate C-C bond. The Sn(IV) atom exhibits a distorted trigonal-bipyramidal coordination environment with the phenyl groups in equatorial positions and the thio-urea and the monodentately bridging oxalate anion in axial positions. The mol-ecules are linked through N-H⋯O hydrogen bonds involving the amino group of the thio-urea ligand and the uncoordinating oxalate O atoms, forming layers parallel to (001). Weak C-H⋯O inter-actions are also present.

In the title compound, [Sn(2)(C(4)H(9))(4)(C(6)H(6)PO(3))(4)](n), the basic unit is a dimer containing two symmetry-related Sn(IV) atoms bridged by two hydrogenphenylphosphonate anions. This fragment is located about an inversion center, and each Sn(IV) atom is linked to two other hydrogenphenylphosphonate anions, giving a layered structure parallel to (010). The coordination geometry for the Sn(IV) atoms is close to octa-hedral. The layers are connected via O-H⋯O hydrogen bonds, generating a three-dimensional network. One butyl group is disordered over two sets of sites, with occupancies of 0.49 (2) and 0.51 (2).

The title salt, [(CH(3))(2)NH(2)][Sn(C(6)H(5))(3)Cl(2)], was obtained as a by-product of the reaction between bis-(dimethyl-ammonium) oxalate and triphenyl-tin chloride. In the stannate anion, the trigonal-bipyramidal coordination environment of the Sn(IV) atom is defined by the phenyl groups in equatorial and the Cl atoms in axial positions. The cations are connected to adjacent anions through N-H⋯Cl and C-H⋯Cl hydrogen-bonding inter-actions, leading to a chain motif parallel to [100].

An uncommon coordination protocol induced by the p-tolylsulfonyl dithiocarbimate ligand (L) [L = p-CH(3)C(6)H(4)SO(2)N[double bond, length as m-dash]CS(2)(2-)] in conjunction with PPh(3) allowed the formation of novel homodimetallic, Cu(2)(PPh(3))(4)L (1), trinuclear heterometallic Cu(2)Ni(L)(2)(PPh(3))(4) (2) and heteroleptic complexes of general formula cis-[M(PPh(3))(2)L] [M = Pd(ii) (3), Pt(ii) (4)]. The complexes have been characterized by microanalysis, mass spectrometry, IR, (1)H, (13)C and (31)P NMR and electronic absorption spectra and single-crystal X-ray crystallography. 2 uniquely consists of square planar, trigonal planar and tetrahedral coordination spheres within the same molecule. In both heteroleptic complexes 3 and 4 the orientation of aromatic protons of PPh(3) ligand towards the Pd(ii) and Pt(ii) center reveals C-HPd and C-HPt rare intramolecular anagostic or preagostic interactions. These complexes exhibit photoluminescent properties in solution at room temperature arising mainly from intraligand charge transfer (ILCT) transitions. The assignment of electronic absorption bands has been corroborated by time dependent density functional theory (TD-DFT) calculations. Complexes 1 and 2 with σ(rt) values ∼ 10(-6) S cm(-1) show semi-conductor properties in the temperature range 313-403 K whereas 3 and 4 exhibit insulating behaviour.

A series of group 4 amine tris(phenolate) complexes have been prepared and characterised by single crystal X-ray diffraction and multinuclear NMR spectroscopy. It was found that the ligands afforded monomeric titanium complexes and dimeric zirconium structures in the solid-state. The complexes have been tested for the ring-opening polymerisation of rac-lactide under both solution and melt conditions, which showed varying degrees of selectivity and control, with PDIs in the range of 1.09-2.07. The initiators were also tested for the production of copolymers containing rac-lactide and isosorbide. From NMR spectroscopic analysis and MALDI-TOF mass spectrometry the isosorbide is incorporated into the polymer. The complexes were also screened for the ring-opening polymerisation of 1,3-dioxan-2-one to produce a polycarbonate with good conversions (24-99%).