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The reaction of a new ligand, ethyl 2,6-diphenylisonicotinate(EtO2C–C∧N∧C–H2), with K2PtCl4in acetic acid affordsthe monocyclometalated complex [{(EtO2C–C∧N∧C–H)Pt(μ-Cl)}2] (1), which transforms to the bis-cyclometalated derivative[Pt(EtO2C–C∧N∧C)(DMSO)] (2) when heated in hot DMSO. Complex 2is the precursor for preparing a new series of neutral mononuclearbis-cyclometalated complexes [Pt(EtO2C–C∧N∧C)(L)] (L = tht (3), PPh3(4), CN-tBu (5), py (6), py-tBu (7), py-NH2(8), py-CN (9), py-CONH2(10)). These new complexes havebeen characterized spectroscopically, and structures of 2–10have been determined crystallographically.Within each crystal structure the individual molecules pack in a head-to-tailarrangement. Noncovalent interactions, including π···π,C–H···O, C–H···N, N–H···Pt,N–H···π, C–H···π,and N–H···O, contribute significantly to thesupramolecular structures displayed by these complexes in the solidstate. All complexes display UV–vis absorptions in dichloromethanesolution. Excitation and emission studies as well as lifetime measurementsare described and can be correlated to the solid-state structuresof the complexes. DFT and TDDFT computational studies have been performedon 5and 8which support the conclusionsdrawn from the photophysical studies. [ABSTRACT FROM AUTHOR]

The reaction between 2- and 3-thienyl-substituted 1,3-butadiynes and the electron-deficient osmium cluster Os3H2(CO)10yields trinuclear coordination products, associated with transformations of the diacetylene ligands. Depending on the heteroaryl end groups, osmium clusters with both a closed and open Os-triangle core were formed. The reaction between Os3H2(CO)10and 1,4-bis(2-thienyl)butadiyne yielded [Os3(μ-H)(CO)10{(μ-η-(C4H3S)(C8H4S)}] (1) and [Os3(μ-H)(CO)10{(μ3-η2-η1-η1-(SC7H4)C(SC4H3)}] (2), whereas in the analogous case of 1,4-bis(3-thienyl)butadiyne the main coordination product was found to be [Os3(μ-H)(CO)10{(μ-η-(C4H3S)(C8H4S)}] (3). Compounds 1–3were stable in air, but lost carbon monoxide upon prolonged heating. Thermal decarbonylation of 1under N2yielded a mixture of [Os3(μ-H)(CO)9{(μ3-η3-(C4H3S)(C8H4S)}] (4) and [Os3(μ-H)2(CO)9{(μ3-η1-η1-(C4H3S)(C8H3S)}] (5). Thermal decarbonylation of 2yielded [Os3(μ-H)(CO)9{(μ3-η3-(C4H3S)(C8H4S)}] (6), while thermal decarbonylation of 3yielded [Os3(μ-H)(CO)9{(μ3-η3-(C4H3S)(C8H4S)}] (7). A reaction involving 3with CF3COOH affords as the main cluster product the known cluster [Os3(μ-H)(CO)10(O2CF3)] (8) and, unusually, permits the isolation and characterization of the novel organic molecule [(C4H3S)(C8H4S)(OCF3)] (9) cleaved from the parent cluster. The structures of the new compounds were established by single-crystal X-ray studies and spectroscopic methods and supported by density functional theory. [ABSTRACT FROM AUTHOR]

Reaction of Al(OiPr)3with the tris-phenol amine ligand L1H3in toluene at ambient temperature results in the formation of the iso-propanol adduct [HOiPr·Al(L1)]. Single crystal X-ray diffraction analysis reveals the structure to be a hydrogen bonded dimer. Reaction of Al(OiPr)3(or AlMe3) with L1H3in THF affords the related, and structurally characterised THF adduct, [THF·Al(L1)]. Similar reaction of Al(OiPr)3(or AlMe3) with the bis-phenol amine and tetra-phenol diamine ligands, L2H3and L3H4, results in the formation and isolation of the complexes [Al(L2)]2and [Al(L3)H] respectively, both of which have been structurally characterised viasingle crystal X-ray diffraction studies. Reaction of the alkoxide bridged dimer [Al(L2)]2with the strong Lewis base HMPA results in the formation of the monomeric HMPA adduct [HMPA·Al(L2)] which was also structurally characterised. The adduct [HOiPr·Al(L1)] and the dimer [Al(L2)]2were tested for their activity in the ring-opening polymerisation (ROP) of rac-lactide under solvent-free conditions (130 °C). Under the conditions employed [Al(L2)]2failed to produce polymer after 48 h, in stark contrast to [HOiPr·Al(L1)] which after 24 h and 48 h produced narrow molecular weight polymer (24 h: yield = 25%, Mn= 14500 and PDI = 1.05; 48 h: yield = 65%, Mn= 47700 and PDI = 1.06). [ABSTRACT FROM AUTHOR]

The synthesis and characterization of the thieno[3,2-b]thiophene and dithieno[3,2-b:2′,3′-d]thiophene containing platinum(II) poly-ynes and their molecular precursors is described and the electronic structure is established by absorption, luminescence and photoinduced absorption measurements. A comparison of the electronic structure of the fused and the nonfused oligothiophenes, thieno[3,2-b]thiophene, dithieno[3,2-b:2′,3′-d]thiophene, 2,2′-bithiophene, and 2,2′:5′,2′′-terthiophene incorporated in platinum(II) poly-ynes is reported. We find the singlet S1and triplet T1and Tnexcited states to be at higher energy in thin films made from the fused systems than from the nonfused systems. For ligands with the same number of rings, we attribute this to the decreased number of double bonds in the fused system and to the presence of an additional sulfur atom in spacers with the same number of double bonds. [ABSTRACT FROM AUTHOR]

CuCN reacts with RLi and TMPLi (TMP = 2,2,6,6-tetramethylpiperidide) to give Gilman-type cuprates R(TMP)CuLi·nL (R = Ph, n= 3, L = THF 2; R = Me, n= 1, L = TMEDA 3). 3and 3·LiCN have been tested in directed ortho cupration with data suggesting enhanced efficiency for Lipshutz-type 3·LiCN; competition between Lipshutz- and Gilman-type formulations is rationalized by DFT methods. [ABSTRACT FROM AUTHOR]

Time-resolved infrared vibrational spectroscopy is a structurally sensitive probe of the excited-state properties of matter. The technique has found many applications in the study of molecules in dilute solution phase but has rarely been applied to crystalline samples. We report on the use of a sensitive pump–probe time-resolved infrared spectrometer and sample handling techniques for studies of the ultrafast excited-state dynamics of crystalline materials. The charge transfer excited states of crystalline metal carbonyls and the proton transfer of dihydroxyquinones are presented and compared with the solution phase. [ABSTRACT FROM AUTHOR]

A series of novel digold complexes incorporating ethynyl pyridine derivatives as a spacer unit, [(R3P)Au(CC)X(CC)Au(PR3)] (R = Ph, X = 2,5-pyridine (1); R = Cy (cyclohexane), X = 2,5-pyridine (2); R = Ph, X = 2,6-pyridine (3); R = Ph, X = 2,5′-bipyridine (4); R = Ph, X = 2,6′-bipyridine (5)), has been synthesised. All the complexes have been characterised spectroscopically and the structures determined by single-crystal X-ray crystallography. The central (CC)(X)(CC) unit is essentially linear for complexes 1, 2 and 4 and kinked for complexes 3 and 5, but only in 1, with the shortest spacer group and the less bulky phosphine ligand, is there evidence of d10⋯d10 Au⋯Au interactions (Au–Au 3.351(2) Å). The solution UV/visible absorption and emission spectra for all the complexes are similar to those of the free ligands suggesting that the spectra are dominated by π–π* ligand-centred transitions and this is confirmed by DFT calculations. [ABSTRACT FROM AUTHOR]

-Benzyl acrylates, which are conveniently prepared from the corresponding aldehydes, can be employed as substrates in a tandem rhodium-catalyzed conjugate addition−enantioselective protonation protocol to afford enantiomerically enriched ,‘-dibenzyl esters. The synergistic effect of enantiopure ligand and proton source was rapidly optimized with use of a microwave reactor. [ABSTRACT FROM AUTHOR]