TY - JOUR A1 - Strehmel, Veronika A1 - Kraudelt, Heide A1 - Wetzel, Hendrik A1 - Görnitz, Eckhard A1 - Laschewsky, André T1 - Free radical polymerization of methacrylates in ionic liquids Y1 - 2004 ER - TY - JOUR A1 - Tahtinen, Petri A1 - Bagno, Alessandro A1 - Koch, Andreas A1 - Pihlaja, Kalevi T1 - Conformational analysis of saturated trans-fused 1,3,2-benzoxazaphosphinine 2-oxides - DFT calculation of NMR J(PH) coupling constants N2 - The (3)J(P,H) and (4)J(P,H) spin-spin coupling constants of a selected test set of organophosphorus compounds, calculated by density functional theory (DFT) methods, were found to correlate well with the experimentally measured coupling constants. The contribution of the spin-dipole (SD) term to the coupling constants was found to be negligible, and the diamagnetic and paramagnetic spin-orbit (DSO and PSO) terms cancelled each other, as in the case of J(H,H). Calculation solely of the Fermi contact (FC) term was found to be sufficient to provide good estimates of the coupling constants. In the second part of the work, the conformational equilibria and coupling constants in 2-bis(2- chloroethyl)amino-trans-octahydro-2H-1,3,2-benzoxazaphosphinine 2-oxide and its 3-methyl derivative were studied. DFT methods failed in predicting the relative stabilities of the conformations but yielded good geometries and coupling constants. Optimization of the conformations at the Moller-Plesset second-order perturbation theory (MP2) level resulted in energy differences compatible with previous experimental observations. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) Y1 - 2004 SN - 1434-193X ER - TY - JOUR A1 - Senge, Mathias O. A1 - Richter, J. T1 - Synthetic, transformations of porphyrins : Advances 2002-2004 N2 - Contemporary methods for the modification of porphyrins are presented. In association with the Third International Conference on Porphyrins and Phthalocyanines (ICPP-3) a survey of current method developments and reactivity studies is made. The review focuses on synthetic transformations of porphyrins currently in use for various applications and on functional group transformations. A brief survey of important developments covers selectively the literature from late 2001 to early 2004. Copyright (c) 2004 Society of Porphyrins C Phthalocyanines Y1 - 2004 SN - 1088-4246 ER - TY - JOUR A1 - Saalfrank, Peter T1 - Theory of photon- and STM-induced bond cleavage at surfaces N2 - In this contribution, recent advances in the theory of laser and, to a lesser extent, of scanning tunneling microscope (STM) induced cleavage of bonds between an adsorbate and a solid surface, will be reviewed. Special emphasis will be given to the quantum dynamics of electronically non-adiabatic reactions. (c) 2005 Elsevier Ltd. All rights reserved Y1 - 2004 SN - 1359-0286 ER - TY - JOUR T1 - Preparation of simple and mixed nickel and cobalt molybdates using hybrid precursors made from an ordered polymer matrix and inorganic salts N2 - The amphiphilic poly(ampholyte) poly(N,N-diallyl-N-hexylamine-alt-maleic acid), bearing simultaneously carboxylic acids, amines and hydrocarbon side chains, was used as a matrix to stabilize inorganic ion species (anionic as well as cationic) generated in aqueous solution from Ni(NO3)(2).6H(2)O, Co(NO3)(2).6H(2)O and (NH4)2MoO(4). Drying produces hybrid organic-inorganic blends which, due to the amphiphilicity of the copolymer, exhibit supramolecular organization in the bulk. Solid state studies show that up to two moles of metal cations (alone or together with metal anions) per repeat unit of the copolymer can be blended without loss of homogeneity in the hybrid material. A systematic screening permitted the determination of the optimal conditions for the preparation of homogeneous blends. Thermal treatment of the hybrid materials produces simple and mixed nickel and/or cobalt molybdates. The alpha- as well as the P- phase were obtained, and the mixed structures are solid solutions of simple NiMoO4 and CoMoO4 Y1 - 2004 ER - TY - JOUR A1 - Peters, Karl A1 - Peters, E. M. A1 - Rebien, F. A1 - Maurer, M. A1 - Linker, Torsten T1 - Crystal structure of (3aS,4S,9R,9aS)-4-hydroxy-9-phenyl-3a,4,9,9a-tetra-hydro-3H-naphtho[2,3- c]furan-1- one,C18H16O3 N2 - C18H16O3, monoclinic, P12(1)/n1 (no. 14), a = 8.284(l) Angstrom, b = 9.524(l) Angstrom, c = 17.729(1) Angstrom, beta = 93.69(1)degrees, V = 1395.9 Angstrom(3), Z = 4, R-gt(F) = 0.052, wR(ref)(F-2) = 0.146, T = 293 K. Y1 - 2004 SN - 1433-7266 ER - TY - JOUR A1 - Peters, Karl A1 - Peters, E. M. A1 - Rebien, F. A1 - Engelhardt, Ulrike A1 - Linker, Torsten T1 - Crystal structure of methyl (1R,4S)-4-hydroxy-1-phenyl-1,4-dihydronaphthalene-2-carboxylate,C18H16O3 N2 - C18H16O3, monoclinic, C12/c1 (no. 15), a = 28.674(4) Angstrom, b = 8.133(1) Angstrom, c = 13.065(2) Angstrom, beta = 108.96(1)degrees, V = 2881.6 Angstrom Z = 8, R-gt(F) = 0.077, wR(ref)(F-2) = 0.245, T = 293 K. Y1 - 2004 SN - 1433-7266 ER - TY - JOUR A1 - Yenesew, Abiy A1 - Induli, M. A1 - Derese, Solomon A1 - Midiwo, Jacob O. A1 - Heydenreich, Matthias A1 - Peter, Martin G. A1 - Akala, Hoseah M. A1 - Wangui, Julia A1 - Liyala, Pamela A1 - Waters, Norman C. T1 - Anti-plasmodial flavonoids from the stem bark of Erythrina abyssinica N2 - The ethyl acetate extract of the stem bark of Erythrina abyssinica showed anti-plasmodial activity against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum with IC50 values of 7.9 +/- 1.1 and 5.3 +/- 0.7 mug/ml, respectively. From this extract, a new chalcone, 2,3,4,4'-tetrahydroxy-5- prenylchalcone (trivial name 5-prenylbutein) and a new flavanone, 4',7-dihydroxy-3'-methoxy-5'- prenylflavanone (trivial name, 5-deoxyabyssinin II) along with known flavonoids have been isolated as the anti- plasmodial principles. The structures were determined on the basis of spectroscopic evidence. (C) 2004 Elsevier Ltd. All rights reserved Y1 - 2004 SN - 0031-9422 ER - TY - JOUR A1 - Wenzel, Barbara A1 - Wehse, Burkhard A1 - Schilde, Uwe A1 - Strauch, Peter T1 - 1,2-Dithioquadratato- und 1,2-Dithiooxalatoindate(III) = 1,2-dithiosquarato- and 1,2-dithiooxalatoindates(III) N2 - Indium(III) chloride forms in water with potassium 1,2-dithiooxalate (dto) and potassium 1,2-dithiosquarate (dtsq) stable coordination compounds. Due to the higher bridging ability of the 1,2-dithiooxalate ligand in all cases only thiooxalate bridged binuclear complexes were found. From 1,2-dithioquadratate with an identical donor atom set mononuclear trischelates could be isolated. Five crystalline complexes, (BzlMe(3)N)(4)[(dto)(2)In(dto)In(dto)(2)] (1), (BzlPh(3)P)(4)[(dto)(2)In(dto)In(dto)(2)] (2), (BzlMe(3)N)(3)[In(dtsq)(3)] (3), (Bu4N)(3)[In(dtsq)(3)] (4) and (Ph4P)[In(dtsq)(2)(DMF)(2)] (5), have been isolated and characterized by X-ray analyses. Due to the type of the complex and the cations involved these compounds crystallize in different space groups with the following parameters: 1, monoclinic in P2(1)/c with a = 14.4035(5) Angstrom, b = 10.8141(5) Angstrom, c = 23.3698(9) Angstrom, beta = 124.664(2)degrees, and Z = 2; 2, triclinic in P (1) over bar with a = 11.3872(7) Angstrom, b = 13.6669(9) Angstrom, c = 17.4296(10) Angstrom, alpha = 88.883(5)degrees, beta = 96.763(1)degrees, gamma = 74.587(5)degrees, and Z = 1; 3, hexagonal in R3 with a = 20.6501(16) Angstrom, b = 20.6501(16) Angstrom, c = 19.0706(13) Angstrom and Z = 6; 4, monoclinic in P21/c with a = 22.7650(15) Angstrom, b = 20.4656(10) Angstrom, c = 14.4770(9) Angstrom, P Y1 - 2004 UR - http://www3.interscience.wiley.com/cgi-bin/jissue/109594384 ER - TY - JOUR A1 - Venkatraman, S. A1 - Kumar, R. A1 - Sankar, J. A1 - Chandrashekar, T. K. A1 - Sendhil, K. A1 - Vijayan, C. A1 - Kelling, Alexandra A1 - Senge, Mathias O. T1 - Oxasmaragdyrin-ferrocene and oxacorrole-ferrocene conjugates : Synthesis, structure, and nonlinear optical properties N2 - Ferrocenyl macrocyclic conjugates involving 22pi oxasmaragdyrins and 18pi oxacorroles have been synthesized and characterized. The direct covalent linkage of the ferrocenyl moiety to the meso position of the macrocycle is achieved by simple oxidative coupling of appropriate precursors with trifluoroacetic acid as catalyst. The electronic coupling between the ferrocenyl moiety and the macrocyclic pi system is apparent from: a) the red shifts (293-718 cm(-1)) of the Soret and Q-bands in the electronic absorption spectra of ferrocenyl conjugates; b) the shift of oxidation potentials (50 130 mV) of both the ferrocene and the corrole rings to the positive potentials; and c) considerable shortening of the C-C bond which connects the ferrocene and the meso-carbon atom of the macrocycle. The single-crystal X-ray structure of oxasmaragdyrin-ferrocene conjugate 9 reveals the planarity of the 22pi skeleton with very small deviations of the meso-carbon atoms. The meso-ferrocenyl substituent has a small dihedral angle of 38degrees, making way for mixing of the molecular orbitals of the ferrocene and the macrocycle. However, the other two meso substituents are almost perpendicular to the mean plane, defined by the three meso carbon atoms. Classical C-(HO)-O-... and nonclassical C- H(...)pi interactions lead to a two-dimensional supramolecular network. Ferrocene-smaragdyrin conjugate 9 bonds to a chloride ion in the protonated form and a rhodium(i) ion in the free base form. Nonlinear optical measurements reveal a larger nonlinear refractive index (-5.83 x 10(-8) cm(2) W-1) and figure of merit (2.28 x 10(-8) cm(3)W(-1)) for the rhodium smaragdyrin-ferrocene conjugate 19 than for the others, suggesting its possible application in optical devices Y1 - 2004 SN - 0947-6539 ER -