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11.
A. V. Makarycheva-Mikhailova S. I. Selivanov N. A. Bokach V. Yu. Kukushkin P. F. Kelly A. J. L Pombeiro 《Russian Chemical Bulletin》2004,53(8):1681-1685
Reactions of the platinum(IV) nitrile complexes [PtCl4(RCN)2] (R = Me, CH2Ph, Ph) with 1,2- and 1,4-PhS(=NH)C6H4SPh in CH2Cl2 afforded addition products of sulfimides and coordinated nitriles, viz., the [PtCl4{NH=C(R)N=S(Ph)(C6H4SPh)}2] complexes. The latter were isolated in 75—90% yields and characterized by elemental analysis, positive-ion FAB mass spectrometry, IR spectroscopy, and 1H and 13C1H NMR spectroscopy. The temperature dependence of the 1H NMR spectra of the model [PtCl4{NH=C(R)N=SPh2}2] complexes (R = Me, Et) in CD2Cl2 studied in a temperature range from +40 to -70 °C demonstrated that E—Z isomerization of the ligands is a dynamic process in a range from +40 to -10 °C. The activation free energy of this process was calculated.Published in Russian in Izvestiya Akademii Nauk.
Seriya Khimicheskaya, No. 8, pp. 1618–1622, August, 2004. 相似文献
12.
Summary Treatment oftrans-[Mo(CNMe)2(PMe2Ph)4] andme-[W(CNMe)3(PMe2Ph)3] with sulphuric or hydrochloric acids in methanol or ethanol, or in methanol alone, under irradiation, gives methylamine, ammonia and hydrocarbons (mainly methane). The complex [W2(CNMe)4(-CNHMe)2(PMe2Ph)4]2+ cation has been obtained by the treatment ofmer-[W(CNMe)3(PMe2Ph3] with H2SO4 or [Et2OH][BF4] and gives methylamine, ammonia and methane on further acid treatment. 相似文献
13.
Wagner G Pakhomova TB Bokach NA Fraústo Da Silva JJ Vicente J Pombeiro AJ Kukushkin VY 《Inorganic chemistry》2001,40(7):1683-1689
A novel method is reported for generation of the difficult-to-obtain (imine)Pt(II) compounds that involves reduction of the corresponding readily available Pt(IV)-based imines by carbonyl-stabilized phosphorus ylides, Ph3P=CHCO2R, in nonaqueous media. The reaction between neutral (imino)Pt(IV) compounds [PtCl4[NH=C(Me)ON=CR1R2]2] [R1R2 = Me2, (CH2)4, (CH2)5, (Me)C(Me)=NOH], [PtCl4[NH=C(Me)ONR2]2] (R = Me, Et, CH2Ph), (R1 = H; R2 = Ph or C6H4Me; R3 = Me) as well as anionic-type platinum(IV) complexes (Ph3PCH2Ph)[PtCl5[NH=C(Me)ON=CR2]] [R2 = Me2, (CH2)4, (CH2)5] and 1 equiv of Ph3P=CHCO2R (R = Me, Et) proceeds under mild conditions (ca. 4 h, room temperature) to give selectively the platinum(II) products (in good to excellent isolated yields) without further reduction of the platinum center. All thus prepared compounds (excluding previously described Delta4-1,2,4-oxadiazoline complexes) were characterized by elemental analyses, FAB mass spectrometry, IR and 1H, 13C[1H], 31P[1H] and 195Pt NMR spectroscopies, and X-ray single-crystal diffractometry, the latter for [PtCl2[NH=C(Me)ON=CMe2]2] [crystal system tetragonal, space group P4(2)/n (No. 86), a = b = 10.5050(10) A, c = 15.916(3) A] and (Ph3PCH2CO2Me)[PtCl3(NCMe)] [crystal system orthorhombic, space group Pna2(1) (No. 33), a = 19.661(7) A, b = 12.486(4) A, c = 10.149(3) A]. The reaction is also extended to a variety of other Pt(II)/Pt(IV) couples, and the ylides Ph3P=CHCO2R are introduced as mild and selective reducing agents of wide applicability for the conversion of Pt(IV) to Pt(II) species in nonaqueous media, a route that is especially useful in the case of compounds that cannot be prepared directly from Pt(II) precursors, and for the generation of systematic series of Pt(II)/Pt(IV) complexes for biological studies. 相似文献
14.
15.
Charmier MA Haukka M Pombeiro AJ 《Dalton transactions (Cambridge, England : 2003)》2004,(17):2741-2745
[PtCl2(RCN)2] (1a R=CH2CO2Me, 1b R=CH2Cl) prepared upon EtCN replacement at [PtCl2(EtCN)2] by the appropriate organonitrile, react with a cyclic nitrone -O-+N=CHCH2CH2C(Me)2, under mild conditions, to give, in an unprecedented single-pot synthesis involving spontaneous N-O bond cleavage, the ketoimino complexes trans-[PtCl2[RC(=O)N=CN(H)C(Me)2-CH2CH2]2 (2a, 2b) with two (pyrrolidin-2-ylidene)amino ligands. The analogous 2c (R=Et) and 2d (R=Ph) are formed by treatment with H2, in the absence of any added catalyst, of the Delta4-1,2,4-oxadiazoline complexes trans-[PtCl2[N=C(R)ONC(Me)2CH2CH2CH]2] (3a R=Et, 3b R=Ph) derived from the [2 + 3]-cycloaddition of the cyclic nitrone with the appropriate organonitrile complex of type 1. The compounds were characterized by elemental analyses, IR, 1H, (13C and 195Pt NMR spectroscopies, FAB mass spectrometry and X-ray structure analyses for 2a and 2d. 相似文献
16.
Makarycheva-Mikhailova AV Bokach NA Kukushkin VY Kelly PF Gilby LM Kuznetsov ML Holmes KE Haukka M Parr J Stonehouse JM Elsegood MR Pombeiro AJ 《Inorganic chemistry》2003,42(2):301-311
Pt(IV)-mediated addition of the sulfimide Ph2S = NH and the mixed sulfide/sulfimides o- and p-[PhS(=NH)](PhS)-C6H4 by the S=NH group to the metal-bound nitriles in the platinum(IV) complexes [PtCl4(RCN)2] proceeds smoothly at room temperature in CH2Cl2 and results in the formation of the heterodiazadiene compounds [PtCl4[NH=C(R)N=SR'Ph]2] (R' = Ph, R = Me, Et, CH2Ph, Ph; R' = o- and p-(PhS)C6H4; R = Et). While trans-[PtCl4(RCN)2] (R = Et, CH2Ph, Ph) reacting with Ph2S=NH leads exclusively to trans-[PtCl4[NH=C(R)N=SPh2]2], cis/trans-[PtCl4(MeCN)2] leads to cis/trans mixtures of [PtCl4[NH=C(Me)N=SPh2]2] and the latter have been separated by column chromatography. Theoretical calculations at both HF/HF and MP2//HF levels for the cis and trans isomers of [PtCl4[NH=C(Me)N=SMe2]2] indicate a higher stability for the latter. Compounds trans-[PtCl4[E-NH=C(R)N=SPh2]2] (R = Me, Et) and cis-[PtCl4[E-NH=C(Me)N=SPh2][Z-NH=C(Me)N=SPh2]] have been characterized by X-ray crystallography. The complexes [PtCl4[NH=C(R)N=SPh2]2] undergo hydrolysis when treated with HCl in nondried CH2Cl2 to achieve the amidines [PtCl4[NH=C(NH2)R]2] the compound with R = Et has been structurally characterized) and Ph2SO. The heterodiazadiene ligands, formed upon Pt(IV)-mediated RCN/sulfimide coupling, can be liberated from their platinum(IV) complexes [PtCl4[NH=C(R)N=SR'Ph]2] by reaction with Ph2PCH2CH2PPh2 (dppe) giving free NH=C(R)=SR'Ph and the dppe oxides, which constitutes a novel route for such rare types of heterodiazadienes whose number has also been extended. The hybrid sulfide/sulfimide species o- and p-[PhS(=NH)](PhS)C6H4 also react with the Pt(II) nitrile complex [PtCl2(MeCN)2] but the coupling--in contrast to the Pt(IV) species--gives the chelates [PtCl2[M-I=C(Me)N=S(Ph)C6H4SPh]]. The X-ray crystal structure of [PtCl2[M-I=C(Me)N=S(Ph)C6H4SPh-o]] reveals the bond parameters within the metallacycle and shows an unusual close interaction of the sulfide sulfur atom with the platinum. 相似文献
17.
Bokach NA Kukushkin VY Kelly PF Haukka M Pombeiro AJ 《Dalton transactions (Cambridge, England : 2003)》2005,(8):1354-1356
Imino(triphenyl)phosphorane, Ph3P=NH (1), reacts with nitrile complexes of Pt(IV) to generate hydrolytically sensitive [PtCl4{NH=C(R)N=PPh3}2](R=Me 2a, Et 2b, Ph 2c), and with the Pt(II) complex [PtCl2(EtCN)2] to give [PtCl2(EtCN){NH=C(Et)N=PPh3}](3) and [PtCl2{NH=C(Et)N=PPh3}2](4); X-ray crystallography performed upon (2b) and (3) confirms the presence of an imine/nitrile addition ligand bound by the terminal nitrogen. 相似文献
18.
Makarycheva-Mikhailova AV Kukushkin VY Nazarov AA Garnovskii DA Pombeiro AJ Haukka M Keppler BK Galanski M 《Inorganic chemistry》2003,42(8):2805-2813
The reaction between the platinum(IV) complex trans-[PtCl(4)(EtCN)(2)] and the amino alcohols NH(2)CH(2)CH(2)OH, NH(2)CH(2)CH(Me)OH-(R)-(-), NH(2)CH(Ph)CH(2)OH-(R)-(-), NH(2)CH(Et)CH(2)OH-(R)-(-), NH(2)CH(Et)CH(2)OH-(S)-(+), and NH(2)CH(Pr(n)())CH(2)OH proceeds rapidly at room temperature in CH(2)Cl(2) to furnish the amidine complexes [PtCl(4)(HN=C(Et)NH(arcraise;)OH)(2)] (1-6) in good yield (70-80%). The related reaction between the platinum(II) complex trans-[PtCl(2)(EtCN)(2)] and monoethanolamine in a molar ratio of 1:2 in CH(2)Cl(2) results in the addition of 4 equiv of NH(2)CH(2)CH(2)OH per mole of complex to give [Pt(HN=C(Et)NHCH(2)CH(2)OH)(2)(NH(2)CH(2)CH(2)OH)(2)](2+) (7). Formulation of 1-6 is based upon satisfactory C, H, N elemental analyses, electrospray mass spectrometry, IR spectroscopy, and (1)H, (13)C((1)H), (15)N, and (195)Pt NMR spectroscopies, while the structures of trans-[PtCl(4)((Z)-NH=C(Et)NHCH(2)CH(2)OH)(2)] (1), trans-[PtCl(4)((Z)-NH=C(Et)NHCH(2)CH(Me)OH-(R)-(-))(2)] (2), and trans-[PtCl(4)((Z)-NH=C(Et)NHCH(Et)CH(2)OH-(R)-(-))(2)] (4) were determined by X-ray single-crystal diffraction. The Z-amidine configuration of the ligands is preserved in CDCl(3) solutions as confirmed by gradient-enhanced (15)N,(1)H-HMQC spectroscopy and NOE experiments. The amidines, formed upon Pt(IV)-mediated nitrile-amino alcohol coupling, were liberated from their platinum(IV) complexes 1, 3, and 4 by reaction with Ph(2)PCH(2)CH(2)PPh(2) (dppe) giving free NH=C(Et)NHCHRCH(2)OH (R = H 8, Et 9, Ph 10), with the substituents R of different types, and dppe oxides; the P-containing species were identified by (31)P((1)H) NMR spectroscopy. NOESY spectroscopy indicates that the liberated amidines retained the same configuration relative to the C=N double bond, i.e., syn-(H,Et)-NH=C(Et)NHCHRCH(2)OH. The liberated hydroxo-functionalized amidines 8-10 were converted into oxazolines (11-13) in the presence of a catalytic amount of ZnCl(2). A similar catalytic effect has also been reached using anhydrous MSO(4) (M = Cu, Co, Cd), CdCl(2), and AlCl(3). 相似文献
19.
José A.L. da Silva João J.R. Fraústo da Silva Armando J.L. Pombeiro 《Coordination chemistry reviews》2011,255(19-20):2232-2248
This contribution is an overview on recent advances (since 2000) on the application of oxovanadium complexes as catalysts or mediators for oxidations by molecular oxygen, peroxidative oxygenations (both including epoxidations), halogenations and carboxylations of aliphatic and aromatic hydrocarbons, and/or olefins, toward the syntheses of a variety of organic compounds, such as alcohols, ketones, epoxides, aldehydes, organohalides and orcarboxylic acids. Some of these systems operate in liquid media, whereas others involve VO-catalysts immobilized on solid supports. 相似文献
20.
Pettinari C Marchetti F Lupidi G Quassinti L Bramucci M Petrelli D Vitali LA da Silva MF Martins LM Smoleński P Pombeiro AJ 《Inorganic chemistry》2011,50(21):11173-11183
Five new silver(I) complexes of formulas [Ag(Tpms)] (1), [Ag(Tpms)(PPh(3))] (2), [Ag(Tpms)(PCy(3))] (3), [Ag(PTA)][BF(4)] (4), and [Ag(Tpms)(PTA)] (5) {Tpms = tris(pyrazol-1-yl)methanesulfonate, PPh(3) = triphenylphosphane, PCy(3) = tricyclohexylphosphane, PTA = 1,3,5-triaza-7-phosphaadamantane} have been synthesized and fully characterized by elemental analyses, (1)H, (13)C, and (31)P NMR, electrospray ionization mass spectrometry (ESI-MS), and IR spectroscopic techniques. The single crystal X-ray diffraction study of 3 shows the Tpms ligand acting in the N(3)-facially coordinating mode, while in 2 and 5 a N(2)O-coordination is found, with the SO(3) group bonded to silver and a pendant free pyrazolyl ring. Features of the tilting in the coordinated pyrazolyl rings in these cases suggest that this inequivalence is related with the cone angles of the phosphanes. A detailed study of antimycobacterial and antiproliferative properties of all compounds has been carried out. They were screened for their in vitro antimicrobial activities against the standard strains Enterococcus faecalis (ATCC 29922), Staphylococcus aureus (ATCC 25923), Streptococcus pneumoniae (ATCC 49619), Streptococcus pyogenes (SF37), Streptococcus sanguinis (SK36), Streptococcus mutans (UA159), Escherichia coli (ATCC 25922), and the fungus Candida albicans (ATCC 24443). Complexes 1-5 have been found to display effective antimicrobial activity against the series of bacteria and fungi, and some of them are potential candidates for antiseptic or disinfectant drugs. Interaction of Ag complexes with deoxyribonucleic acid (DNA) has been studied by fluorescence spectroscopic techniques, using ethidium bromide (EB) as a fluorescence probe of DNA. The decrease in the fluorescence of DNA-EB system on addition of Ag complexes shows that the fluorescence quenching of DNA-EB complex occurs and compound 3 is particularly active. Complexes 1-5 exhibit pronounced antiproliferative activity against human malignant melanoma (A375) with an activity often higher than that of AgNO(3), which has been used as a control, following the same order of activity inhibition on DNA, i.e., 3 > 2 > 1 > 5 > AgNO(3)? 4. 相似文献