الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Charge-transfer complexes formed in the reaction of the mixed oxygen–nitrogen cyclic base, N,N´-dibenzyl-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane (DD18C6) with iodine as a ?-acceptor and with other different ?-acceptors, have been studied spectrophotometrically at room temperature in CHCl3. The ?-acceptors used in this investigation are 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), picric acid (PA) and 7,7´,8,8´-tetracyanoquinodimethane (TCNQ). The obtained CT-complexes are formulated as [DD18C6?H2]I8 (1), [(DD18C6)(DDQ)4] (2), [(DD18C6)(PA)4] (3) and [(DD18C6)(TCNQ)2] (4). In a similar way, other CT-complexes are formed during the reactions of hexamethylenetetramine (HMTA) with the ?-acceptors (PA, chloranilic acid; ChlA, DDQ, tetracyanoethylene; TCNE) to form [(HMTA)(PA)] (5), [(HMTA)(ChlA)] (6), [(HMTA)(DDQ)2] (7), [(HMTA)(TCNE)2] (8). Hexamethyl-hexacyclene (HMHCY) reacts with the acceptors I2, DDQ, PA and TCNQ to form complexes of the general formula [(HMHCY)(Acceptor)4] (9?12). 2,9-Dimethyl-1,10-phenanthroline (Me2phen) reacts with iodine to form [Me2phenH]I5 (13) and with ?-acceptors PA, ChlA and Chl to form [(Me2phen)(PA)] (14), [(Me2phen)(ChlA)] (15) and [(Me2phen)(Chl)] (16), respectively. The obtained results indicate the formation of 1:1, 1:2 or 1:4 donor–acceptor CT-complexes. The obtained charge-transfer complexes are investigated by UV-Vis. and infrared spectroscopy. X-ray structures of some complexes (1, 5, 13, 15) as well as Raman spectra of iodine complexes, 1, 9 and 13 are obtained and discussed.
The second part of this investigation, comprises the syntheses via ligand substitution, spectroscopic characterization, and subsequent structure determination by single crystal X-ray diffraction methods of Pt(IV) complexes formed by the reaction of {H2[PtCl6]?6H2O (17), (H3O)[PtCl5(H2O)]?2(18C6)?6H2O (18) (18C6 = crown ether 18-crown-6)} as starting materials with various donors (bpy and phen derivatives, bpym and terpy) which acted as bi- and tridentate ligand donors. Different reaction products, [PtCl4(bpy)] (19), [PtCl4(tBu2bpy)] (20), (phenH)2[PtCl6] (21), (Ph2phenH)2[PtCl6] (22), [PtCl4(Ph2phen)] (23), [PtCl2(Ph2phen)] (24), [PtCl4(bpym)] (25) [PtCl2(bpym)] (26), [PtCl3(terpy)]2[PtCl6] (27) were isolated and fully characterized.
The third part focus on the synthesis of platinum(IV) complexes with nucleobase ligands via ligand substitution reactions. Depending on the reaction conditions, H2[PtCl6]?6H2O (17) and (H3O)[PtCl5(H2O)]?2(18C6)?6H2O (18) react with MeAde and Ado yielding hexachloroplatinate salts with protonated 9-methyladeninium/ adenosinium cations, (MeAdeH)2[PtCl6]?2H2O (28b), (AdoH)2[PtCl6] (29c) or platinum(IV) complexes with N1 protonated N7 bonded 9-methyladenine/ adenosine ligands; [PtCl5(MeAdeH-kN7)]?1/2(18C6)?H2O (28a), [PtCl5(AdoH-kN7)]?(18C6)?H2O (29a), [PtCl5(MeAdeH-kN7)] (28c) and [PtCl5(AdoH-kN7)] (29b). In an analogous way, further Pt(IV) complexes, (MeGuaH)2[PtCl6]?2H2O (30), [PtCl5(GuaH-kN9)]?3/2(18C6)?H2O (31a), [PtCl5(GuoH-kN7)]?3H2O (31b), (GuoH)2[PtCl6] (31c), [PtCl3(GuaH-kN9)]?(18C6)?2Me2CO (31e), (MeCytH)2[PtCl6]?2H2O (32a), (CydH)2-[PtCl6] (32b) are obtained by the reaction with 9-methylguanine, guanosine, 1-methylcytosine and cytidine, respectively. All platinum(IV) complexes were fully characterized by microanalysis, IR, (1H, 13C, 195Pt) NMR spectroscopies, partially by solid state 195Pt NMR and single crystal X-ray crystallography. The coordination modes of Pt(IV) complexes with these ligands and redox stability are discussed. Such types of complexes exhibit widely varying properties, including analytical, biological, and medical as well as photo- and electrochemical.