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Theoretical studies on the lanthanide and actinide triflate complexes M(OTf) where M = La, Ce, Gd, Yb, Lu, Th, U, Np, Pu, Am, Cm, Bk, and No; n = 3 and 4, are carried out using functional density theory (DFT). The study of An(OTf) complexes showed that the three OTf groups are bidentate, generating a trigonal prism (TP). Two limiting structures of TP are observed; the most distorted is the thorium triflate Th(OTf) and the ideal one is U(OTf). The highest population contribution of 5 d orbital compared to 5 f orbital in Th-O bond of Th(OTf) explains the distortion. The intramolecular rearrangement of the OTf ligands in Ln(OTf) generates two conformers. In Yb(OTf), the pseudo-eclipsed and the staggered conformations are stable and can be isolated. [ABSTRACT FROM AUTHOR]

Two novel triflate precursors for radiolabelling of L-tyrosine in positron emission tomography (PET) for tumor imaging, O-(2-trifluoromethanesulfonyloxyethyl)- N-( tert-butoxycarbonyl)- L-tyrosine methyl ester 9a and O-(2-trifluoromethanesulfonyloxyethyl)- N-( tert-butoxycarbonyl)- L-tyrosine tert-butyl ester 9b, are synthesized. The triflate agent, 9a or 9b, is prepared by esterification of methanol or transesterification of tert-butyl acetate with L-tyrosine, protection of the amine group with di- tert-butyl dicarbonate, alkylation with chlorohydrin, and triflation with trifluoromethanesulfonic anhydride in four steps with overall yields of 30% and 15%, respectively. [ABSTRACT FROM AUTHOR]

The new salts of pyridine-4-aldehyde thiosemicarbazone: perchlorate (I) and trifluoromethane sulfonate (II) HN+C5H4-CH=N-NH-C(S)-NH2·X− (X = ClO4, CF3SO3) were synthesized and studied by IR and NMR spectroscopy and X-ray diffraction analysis. The compounds were synthesized by a reaction of pyridine-4-aldehyde thiosemicarbazone with chloric or trifluoromethane sulfonic acid, respectively. Compound I crystallized in the triclinic crystal system, space group P-1, a = 6.8691(2) Å, b = 9.5406(4) Å, c = 9.6348(4) Å, α = 78.838(1)°, β = 77.618(1)°, γ = 69.661(1)°, Z = 2. Compound II crystallized in the monoclinic crystal system, space group P21/ c, a = 7.3149(8) Å, b = 11.9830(16) Å, c = 15.143(2) Å, β= 96.949(4)°, Z = 4. The structures are formed by hydrogen-bonded ions. Moreover, the cations are linked in “dimmers” due to the weak N-H...S hydrogen bonds. [ABSTRACT FROM AUTHOR]

A new copper(II) coordination compound with the ligand 2,2′-bipyridine- N-oxide (abbreviated as bpyNO), Cu(bpyNO)2(CF3SO3)2, is described. This compound is investigated in detail by spectroscopy, EPR and X-ray crystal structure analysis. The compound crystallizes in the monoclinic space group P21/ n with a = 6.554(1) Å, b = 13.681(3) Å, c = 14.935(3) Å, β = 98.77(3)°, Z = 2. The copper has an axial elongated octahedral geometry with the basal plane formed by two trans-orientated bpyNO molecules with Cu_N distance of 2.008(2) Å and a Cu_O distance of 1.950(2) Å. The axial positions are occupied by oxygen atoms of two trans-oriented triflate anions with a Cu_O distance of 2.397(2) Å. [ABSTRACT FROM AUTHOR]

The article describes maltol tosylate and triflate prossessing nonlinear optical properties. Tosyl chloride and trifluoromethanesulfonyl fluoride react with sodium maltol, which was prepared from maltol and metallic sodium in absolute dioxane, to give good yields of the maltol tosylate and triflate. A second harmonic emission of a neodymium laser is generated with an efficiency comparable with that for the classical nonlinear optical material lithium iodate.