Synthesis and properties of pentamethylmetallocene derivatives Cp*MCp (M = Ru, Fe). Crystal structure of the salt [CpRuC5Me4CH2+OC6H2(NO2)3-]

Photolysis of a solution of Cp*RuCp (1) in CF₃CO₂H generates salt [CpRu(C₅Me₄CH₂)]-(O₂CCF₃)(2 • O₂CCF₃). The reaction of compound 1 with oleum at 20 °C through the intermediate dication [η⁵-(CH₂C₅Me₄)Ru(μ:η⁵,ν⁵-C₅H₄C₅H₅)Ru(C₅Me₄CH₂)-η⁶]²⁺ leads to the triply charged cation η⁷CH₂)₂C₅Me₃Ru(μη⁵,η⁵-C₅H₄C₅H₄)Ru(C₅Me₄CH₂)-η⁶]³⁺. Synthesis of pentamethylmetallocene derivatives CpMC₅Me₄X (M = Ru, Fe; X = CHO, CH₂OH, CH₂An) has been accomplished. The reactions of 1-hydroxymethyl-2,3,4,5-tetramethylruthenocene with acids CF₃CO₂H, HBF₄, CF₃CO₂H/NaB[C₆H₃(CF₃)₂]₄, and picric acid C₆H₂(NO₂)₃OH afforded salts 2•X (X = CF₃CO₂, BF₄, B[C₆H₃(CF₃)₂]₄), and (2,3,4,5-tetram ethylruthenocenyl)methyl picrate [CpRu(C₅Me₄CH₂)-η⁶][(C₆H₂(NO₂)₃O] (2•C₆H₂(NO₂)₃O). Structure of the latter was characterized by single crystal X-ray diffraction.     

Syntheses,spectroscopic study and crystal structures of some new <Emphasis Type="Italic">N</Emphasis>-benzoylphosphoric triamides

The reaction of N-benzoylphosphoramidic dichloride with amines afforded some new N-benzoylphos-phoric triamides with formula C₆H₅C(O)NHP(O)(X)₂, X=NH–CH(CH₃)₂ (1), NH–CH₂–CH(CH₃)₂ (2), NH–CH₂–CH(OCH₃)₂ (3), N(CH₃)[CH₂CH(OCH₃)₂] (4) and N(CH₃)(C₆H₁₁) (5) that were characterized by ¹H,¹³C,³¹P NMR, IR spectroscopy and elemental analysis. The structures have been determined for compounds 4 and 5 by X-ray crystallography. These compounds contain one amidic hydrogen atom and form centrosymmetric dimmers via intermolecular –P–O⋯H–N–hydrogen bonds besides weak C–H⋯O hydrogen bonds that lead to three-dimensional polymeric clusters in the crystalline lattice.     

Synthesis and Anticancer Activity of Long-Chain Isonicotinic Ester Ligand-Containing Arene Ruthenium Complexes and Nanoparticles

Arene ruthenium complexes containing long-chain N-ligands L¹ = NC₅H₄–4-COO–C₆H₄–4-O–(CH₂)₉–CH₃ or L² = NC₅H₄–4-COO–(CH₂)₁₀–O–C₆H₄–4-COO–C₆H₄–4-C₆H₄–4-CN derived from isonicotinic acid, of the type [(arene)Ru(L)Cl₂] (arene = C₆H₆, L = L¹: 1; arene = p-MeC₆H₄Pr ⁱ , L = L¹: 2; arene = C₆Me₆, L = L¹: 3; arene = C₆H₆, L = L²: 4; arene = p-MeC₆H₄Pr ⁱ , L = L²: 5; arene = C₆Me₆, L = L²: 6) have been synthesized from the corresponding [(arene)RuCl₂]₂ precursor with the long-chain N-ligand L in dichloromethane. Ruthenium nanoparticles stabilized by L¹ have been prepared by the solvent-free reduction of 1 with hydrogen or by reducing [(arene)Ru(H₂O)₃]SO₄ in ethanol in the presence of L¹ with hydrogen. These complexes and nanoparticles show a high anticancer activity towards human ovarian cell lines, the highest cytotoxicity being obtained for complex 2 (IC₅₀ = 2 μM for A2780 and 7 μM for A2780cisR).     

Oxygen- versus carbon-coordination of the alpha-stabilized phosphorus ylide Ph<Subscript>3</Subscript>P=C(H)R in palladacycles bearing secondary amines

The ortho-metalated complex [Pd(x){κ ² (C,N)-[C₆H₄CH₂NRR′ (Y)}] (2a–4a and 2b–3b) was prepared by refluxing in benzene equimolecular amounts of Pd(OAc)₂ and secondary benzylamine [a, EtNHCH₂Ph; b, t-BuNHCH₂Ph followed by addition of excess NaCl. The reaction of the complexes [Pd(x){κ ² (C,N)-[C₆H₄CH₂NRR′ (Y)}] (2a–4a and 2b–3b) with a stoichiometric amount of Ph₃P=C(H)COC₆H₄-4-Z (Z = Br, Ph) (ZBPPY) (1:1 molar ratio), in THF at low temperature, gives the cationic derivatives [Pd(OC(Z-4-C₆H₄C=CHPPh₃){κ ² (C,N)-[C₆H₄CH₂NRR′(Y)}] (5a–9a, 4b–6b, and 4b′–6b′), in which the ylide ligand is O-coordinated to the Pd(II) center and trans to the ortho-metalated C(6)H(4) group, in an “end-on carbonyl”. Ortho-metallation, ylide O-coordination, and C-coordination in complexes (5a–9a, 4b–6b, and 4b′–6b′) were characterized by elemental analysis as well as various spectroscopic techniques.     

Different coordination modes of trans‐2‐{[(2‐methoxyphenyl)imino]methyl}phenoxide in rare‐earth complexes: influence of the metal cation radius and the number of ligands on steric congestion and ligand coordination modes

A simple and effective synthetic route to homo‐ and heteroleptic rare‐earth (Ln = Y, La and Nd) complexes with a tridentate Schiff base anion has been demonstrated using exchange reactions of rare‐earth chlorides with in‐situ‐generated sodium (E)‐2‐{[(2‐methoxyphenyl)imino]methyl}phenoxide in different molar ratios in absolute methanol. Five crystal structures have been determined and studied, namely tris(2‐{[(2‐methoxyphenyl)imino]methyl}phenolato‐κ³O¹,N,O²)lanthanum, [La(C₁₄H₁₂NO₂)₃], ( 1 ), tris(2‐{[(2‐methoxyphenyl)imino]methyl}phenolato‐κ³O¹,N,O²)neodymium tetrahydrofuran disolvate, [La(C₁₄H₁₂NO₂)₃]·2C₄H₈O, ( 2 )·2THF, tris(2‐{[(2‐methoxyphenyl)imino]methyl}phenolato)‐κ³O¹,N,O²;κ³O¹,N,O²;κ²N,O¹‐yttrium, [Y(C₁₄H₁₂NO₂)₃], ( 3 ), dichlorido‐1κCl,2κCl‐μ‐methanolato‐1:2κ²O:O‐methanol‐2κO‐(μ‐2‐{[(2‐methoxyphenyl)imino]methyl}phenolato‐1κ³O¹,N,O²:2κO¹)bis(2‐{[(2‐methoxyphenyl)imino]methyl}phenolato)‐1κ³O¹,N,O²;2κ³O¹,N,O²‐diyttrium–tetrahydrofuran–methanol (1/1/1), [Y₂(C₁₄H₁₂NO₂)₃(CH₃O)Cl₂(CH₄O)]·CH₄O·C₄H₈O, ( 4 )·MeOH·THF, and bis(μ‐2‐{[(2‐methoxyphenyl)imino]methyl}phenolato‐1κ³O¹,N,O²:2κO¹)bis(2‐{[(2‐methoxyphenyl)imino]methyl}phenolato‐2κ³O¹,N,O²)sodiumyttrium chloroform disolvate, [NaY(C₁₄H₁₂NO₂)₄]·2CHCl₃, ( 5 )·2CHCl₃. Structural peculiarities of homoleptic tris(iminophenoxide)s ( 1 )–( 3 ), binuclear tris(iminophenoxide) ( 4 ) and homoleptic ate tetrakis(iminophenoxide) ( 5 ) are discussed. The nonflat Schiff base ligand displays μ₂‐κ³O¹,N,O²:κO¹ bridging, and κ³O¹,N,O² and κ²N,O¹ terminal coordination modes, depending on steric congestion, which in turn depends on the ionic radii of the rare‐earth metals and the number of coordinated ligands. It has been demonstrated that interligand dihedral angles of the phenoxide ligand are convenient for comparing steric hindrance in complexes. ( 4 )·MeOH has a flat Y₂O₂ rhomboid core and exhibits both inter‐ and intramolecular MeO—H…Cl hydrogen bonding. Catalytic systems based on complexes ( 1 )–( 3 ) and ( 5 ) have demonstrated medium catalytic performance in acrylonitrile polymerization, providing polyacrylonitrile samples with narrow polydispersity.     

Mixed-ligand iridium(IV) complexes with amino acids,adenine and hypoxanthine

The complexation in iridium(IV)-purine base (adenine, hypoxanthine)-amino acid (α-alanine, aspartic acid, lysine) systems was studied by pH titration. The stability constants of 1: 1: 1 complexes were determined. The stability of 1: 1: 1 mixed-ligand complexes with hypoxanthine and adenine increases in the series Ala < Lys < Asp. Reactions between aqueous solutions gave the following coordination compounds: [Ir(C₅H₄N₄O)(C₃H₆NO₂)Cl]Cl₂, [Ir(C₅H₄N₄O)(C₄H₅NO₄)]Cl₂, [Ir(C₅H₄N₄O)(C₆H₁₃N₂O₂)]Cl₃, [Ir(C₅H₅N₅)(C₃H₆NO₂)]Cl₃, [Ir(C₅H₅N₅)(C₄H₅NO₄)]C_l2, and [Ir(C₅H₅N₅)(C₆H₁₃N₂O₂)]Cl₃. The individual character of the complexes was established by chemical and thermogravimetric analyses and powder X-ray diffraction. The complexes were characterized by NMR, IR, and X-ray photoelectron spectroscopy. Alanine and lysine in mixed-ligand iridium(IV) complexes are bidentate (α-NH₂ and COO⁻ groups), aspartic acid is tridentate, and purine bases function as polydentate ligands through heterocycle N atoms and functional groups (NH₂ in adenine and C=O in hypoxanthine).     

Functionalized cyclopalladated compounds with bidentate Group 15 donor atom ligands: the crystal and molecular structures of [{Pd[5-(COH)C6H3C(H)NCy-C2,N](Cl)}2(μ-Ph2PRPPh2)] (R=CH2CH2, Fe(C5H4)2], [Pd{5-(COH)C6H3C(H)NCy-C2,N}(Ph2PCH2PPh2-P,P)][PF6] and [Pd{5-(COH)C6H3C(H)N(Cy)-C2,N}(Ph2PCH2CH2AsPh2-P,As)][PF6]

The chloro-bridged dinuclear compound [{Pd[5-(COH)C₆H₃C(H)N(Cy)-C2,N]}(μ-Cl)]₂ (1), reacts with tertiary diphosphines in 1:1 molar ratio to give [{Pd[5-(COH)C₆H₃C(H)NCy-C2,N](Cl)}₂(μ-Ph₂PRPPh₂)] (R: CH₂, 2; CH₂CH₂, 3; (CH₂)₄, 4; (CH₂)₆, 5; Fe(C₅H₄)₂, 6; trans-CHCH, 7; C≡C, 8). Treatment of 1 with Ph₂PCH₂CH₂AsPh₂ (arphos) gives the dinuclear complex [{Pd[5-(COH)C₆H₃C(H)N(Cy)-C2,N](Cl)}₂(μ-Ph₂PCH₂CH₂AsPh₂)] (9). The reaction of 1 with tertiary diphosphines or arphos in 1:2 molar ratio in the presence of NH₄PF₆ yields the mononuclear compounds [Pd{5-(COH)C₆H₃C(H)NCy-C2,N}(Ph₂PRPPh₂-P,P)][PF₆] (R: (CH₂)₄, 10; (CH₂)₆, 11; Fe(C₅H₄)₂, 12; 1,2-C₆H₄, 13; cis-CHCH, 14; NH, 15) and [Pd{5-(COH)C₆H₃C(H)N(Cy)-C2,N}(Ph₂PCH₂CH₂AsPh₂-P,As)][PF₆] (16). ¹H-, ³¹P-{¹H}- and ¹³C-{¹H}-NMR, IR and mass spectroscopic data are given. The crystal structures of compounds 3, 6, 9 and 16 have been determined by X-ray crystallography.     

O-Tolyl/benzyl dithiocarbonates of phosphorus(III) and (V): syntheses and characterization

Abstract  

O-Tolyl/benzyl dithiocarbonates, ROCS₂Na (R = o-, m-, or p-CH₃C₆H₄–, and –CH₂C₆H₅), were synthesized and characterized. These new ligands reacted with PCl₃/POCl₃ in refluxing toluene which resulted in the formation of phosphorus(III) and phosphorus(V) tolyl/benzyl dithiocarbonates corresponding to [(ROCS₂) _n PCl_3−n ] and [(ROCS₂) _n POCl_3−n ] (R = o-, m-, or p-CH₃C₆H₄–, and –CH₂C₆H₅; n = 1, 2, 3). These pale yellow liquid compounds were characterized by IR, mass, and NMR (¹H, ¹³C, and ³¹P) spectral studies, which suggest the dithiocarbonate ligands bind in a monodentate mode leading to P–S–C linkages in these derivatives.     

A novel series of gold(III)-bis-triphenylphosphine-arylazoimidazole complexes: synthesis and spectroscopic and redox study

Reaction of [Au(PPh₃)₂(tht)₂](OSO₂CF₃)₃ with RaaiR′ in CH₂Cl₂ medium following ligand addition leads to [Au(PPh₃)₂(RaaiR′)](OTf)₃ [RaaiR′ = p-R–C₆H₄–N=N–C₃H₂–NN–1–R′, (1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1), CH₂CH₃ (2), CH₂Ph (3), PPh₃ is triphenylphosphine, OSO₂CF₃ is the triflate anion, tht is tetrahydrothiophen]. The maximum molecular peak of the corresponding molecule is observed in the ESI mass spectrum. The ¹H-nmr spectral measurements suggest methylene, –CH₂–, in RaaiEt gives a complex AB type multiplet while in RaaiCH₂Ph it shows AB type quartets. ¹³C-nmr spectrum suggests the molecular skeleton. In the ¹H–¹H COSY spectrum as well as contour peaks in the ¹H–¹³C heteronuclear multiple-quantum coherence (HMQC) spectrum assign the solution structure. Electrochemistry assign ligand reduction part rather than metal oxidation.     

Reactivity of diacetylplatinum(II) complexes: oxidative addition of alkyl halides and crystal structures of acetyl platinum(IV) complexes

Diacetylplatinum(II) complexes [Pt(COMe)₂(N^N)] (N^N = bpy, 3a; 4,4′-t-Bu₂-bpy, 3b) were found to undergo oxidative addition reactions with organyl halides. The reaction of 3a with methyl iodide and propargyl bromide led to the formation of the cis addition products (OC-6-34)-[Pt(COMe)₂(R)X(bpy)] (R = Me, X = I, 4a; CH₂C≡CH, X = Br, 4k). Analogous reactions of 3a with ethyl iodide, benzyl bromide, and substituted benzyl bromides, 3-(bromomethyl)pyridine, 2-(bromomethyl)thiophene, allyl bromide, and cyclohex-2-enyl bromide led to exclusive formation of the trans addition products (OC-6-43)-[Pt(COMe)₂(R)X(bpy)] (X = I, R = Et, 4b; X = Br, R = CH₂C₆H₅, 4c; CH₂C₆H₄(o-Br), 4d; CH₂C₆H₄(p-COOH), 4e; CH₂-3-py (3-pyridylmethyl), 4f; CH₂-2-tp (2-thiophenylmethyl), 4g; CH₂CH=CH₂, 4h; c-hex-2-enyl (cyclohex-2-enyl), 4i). All complexes 4 were characterized by microanalysis, ¹H and ¹³C NMR and IR spectroscopy. Additionally, complexes 4a, 4f, and 4g were characterized by single-crystal X-ray diffraction analyses. Reactions of 3a and 3b with o-, m- and p-bis(bromomethyl)benzene, respectively, led to the formation of dinuclear platinum(IV) complexes [{Pt(COMe)₂Br(N^N)}₂-{μ-(CH₂)₂C₆H₄}] (5). These complexes were characterized by microanalysis, IR spectroscopy, and depending on their solubility by ¹H and ¹³C NMR spectroscopy, too. A single-crystal X-ray diffraction analysis of complex [{Pt(COMe)₂Br(bpy)}₂{μ-m-(CH₂)₂C₆H₄}] (5b) confirmed its dinuclear composition. The solid-state structures of 4a, 4f, 4g, and 5b are discussed in terms of C–H···O and O–H···O hydrogen bonds as well as π–π stacking between aromatic rings.     

Novel and chemoselective one-pot synthesis of 4-arylidene-2-phenyl-5(4H)-oxazolones starting from benzyl alcohols promoted by [(C14H24N4)2W10O32]-[bmim]NO3

Abstract  

A new and practical promoter system for one-pot, efficient, chemoselective synthesis of 4-arylidene-2-phenyl-5(4H)-oxazolones using [(C₁₄H₂₄N₄)₂W₁₀O₃₂]-[bmim]NO₃ under solvent-free conditions is described. The present work opens up a new and ecofriendly synthetic route to Erlenmeyer–Pl?chl adducts from primary benzyl alcohols in a one-pot operation.     

Oxidation of γ-stannyl sulfides by monochloramine CB and hydrogen peroxide

The first γ-trimethylstannyl sulfimide, Me³Sn(CH₂)₃S(=NSO₂Ar)C₅H₁₁-n, was synthesized by oxidative imination of Me₃Sn(CH₂)₃SC₅H₁₁-n with ArSO₂(Na)Cl (Ar=C₆H₄Cl-4). Oxidation of γ-trimethylstannyl sulfimide by an alkaline solution of H₂O₂ gave γ-trimethylstannyl sulfoximide, Me₃Sn(CH₂)₃S(O)(=NSO₂Ar)C₅H₁₁-n, and γ-trimethylstannyl sulfone, Me₃Sn(CH₂)₃SO₂C₅H₁₁-n, the latter compound resulting from hydrolysis of the arylsulfimide group. Oxidation of stannyl sulfide by hydrogen peroxide yielded γ-trimethylstannyl sulfoxide, Me₃Sn(CH₂)₃S(O)C₅H₁₁-n (under mild conditions) or γ-trimethylstannyl sulfone (under more severe conditions). Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 371–374, February, 1997.     

The electrochemical properties of a platinum electrode in functionalized room temperature imidazolium ionic liquids

The electrochemical behavior of a platinum electrode in a set of 1-alkyl ether (and 1-alkyl)-3-methylimidazolium room-temperature ionic liquids (RTILs) 1–3 ([C_xO_yMim]⁺[Anion]⁻ or [C_xMim]⁺[Anion]⁻, where Mim = 3-methylimidazolium; C_xO_y = 1-alkyl ether; C₇O₃ = -(CH₂)₂O(CH₂)₂O(CH₂)₂OCH₃; C₃O₁ = -(CH₂)₂OCH₃; C_x = 1-alkyl; C₁₀ = C₁₀H₂₁; C₄ = C₄H₉; and ) was studied by cyclic voltammetry and electrical conductivity. This complementary set of imidazolium RTILs allowed us to explore the effect of the imidazolium cation and the counter-ion, both of which affected the electrochemical window of these RTILs. Various electrochemical events with low current values were observed, which diminished the electrochemical windows. Interestingly, RTILs 2b [1-(2-methoxyethyl)-3-methylimidazolium tetrafluoroborate] and 2d [1-butyl-3-methylimidazolium tetrafluoroborate] showed quasireversible charge transfer processes. The length of the functional group attached to the imidazolium cation was shown to be of great influence as larger electrochemical windows, as well as lower electrical conductivities, were obtained with the longer C₇O₃ and C₁₀ functional groups. The largest electrochemical window of 2.0 V was achieved with RTIL 2c, 1-decyl-3-methylimidazolium tetrafluoroborate. Dedicated to the memory of Prof. Francisco Nart.     

o-Phenylene-bridged Cp/amido titanium and zirconium complexes and their polymerization reactivity

o-Phenylene-bridged trimethylcyclopentadienyl/amido titanium complexes [(η⁵-2,3,5-Me₃C₅H)C₆H₄NR-κN]TiCl₂ (18, R = CH₃; 19, R = CH₂CH₃; 20, R = CH₂C(CH₃)₃; 21, R = CH₂(C₆H₁₁)) and zirconium complexes {[(η⁵-2,3,5-Me₃C₅H)C₆H₄NR-κN]ZrCl-μCl}₂ (22, R = CH₃; 23, R = CH₂CH₃; 24, R = CH₂C(CH₃)₃; 25, R = CH₂(C₆H₁₁); 26, R = C₆H₁₁; 27, R = CH(CH₂CH₃)₂) are prepared via a key step of the Suzuki-coupling reaction between 2-dihydroxyboryl-3-methyl-2-cyclopenten-1-one (2) and the corresponding bromoaniline compounds. The molecular structures of titanium complexes 18 and 19 and dinuclear zirconium complexes 24 and 26 were confirmed by X-ray crystallography. The Cp(centroid)-Ti-N and Cp(centroid)-Zr-N angles are smaller, respectively, than those observed for the Me₂Si-bridged complex [Me₂Si(η⁵-Me₄C₅)(N^tBu)]TiCl₂ and its Zr-analogue, indicating that the o-phenylene-bridged complexes are more constrained than the Me₂Si-bridged complex. Titanium complex 19 exhibits comparable activity and comonomer incorporation to the CGC ([Me₂Si(η⁵-Me₄C₅)(N^tBu)]TiCl₂) in ethylene/1-octene copolymerization. Complex 19 produces a higher molecular-weight polymer than CGC.     

Darstellung und eigenschaften von diorganogermaniumdisulfinsäureestern

Diorganogermaniumdisulfinic esters of the type R₂Ge(O₂SR′)₂ (R = CH₃, R′ = CH₃, C₆H₅, p-CH₃C₆H₄; R = C₆H₅, R′ = CH₃, p-CH₃C₆H₄) which are sensitive to hydrolysis are obtained by reaction of the corresponding diorganogermanium dichlorides with anhydrous silver sulfinates. The newly prepared compounds are thoroughly investigated on the basis of their ¹H NMR, mass, IR and Raman spectra. The methyl ester (CH₃)₂Ge(O₂SCH₃)₂ is compared with the already known sulfinato complex of tin with the same formal composition.     

Modification of supramolecular assemblies based on C4H7(CH3)Te heterocycle and cooperative participation of intermolecular I···I, Te···I, Te···O secondary bonds; C(sp3)–H···O and C(sp2)–H···O hydrogen bonds

2-Methyl-1,1-dicarboxylato-1-telluracyclopentanes C₄H₇(CH₃)Te(OCOR)₂ (R=OCO, C₆H₅, 4-NO₂C₆H₄, 3,5-(NO₂)₂C₆H₃, C₆H₅CH=CH, 4-OCH₃C₆H₄) (2–7) were synthesised from the reactions of 2-methyl-1,1-diiodo-1-telluracyclopentane (1) and corresponding silver salts and characterised by (IR &¹HNMR) spectroscopy. The structures of C₄H₇(CH₃)TeI₂ (1), C₄H₇(CH₃)Te(OCOC₆H₅)₂ (3) and C₄H₇(CH₃)Te(4-NO₂C₆H₄OCO)₂ (4) were established by single crystal X-ray diffraction studies. The structures of 1, 3 & 4 (the immediate environment about tellurium is that of distorted trigonal bipyramidal geometry with a stereochemically active electron lone pair) are described in the context of their ability to generate intermolecular I···I, Te···I, Te···O secondary bonds; C(sp³)–H···O and C(sp²)–H···O hydrogen bonds leading to the formation of polymeric, tetrameric and trimeric supramolecular assemblies. The modification of supramolecular assembly present in the precursor 1 is demonstrated and the cooperative participation of C(sp²)–H···O & C(sp³)–H···O hydrogen bonds, probably, helpful in strengthening the supramolecular assembly is discussed.

Alkaloids ofBuxus balearica. I

Conclusions Seven alkaloids have been isolated from the leaves ofBuxus balearica Lam: alkaloid A (apparently identical with baleabuxine), C₃₀H₅₀N₂O₂; alkaloid B (possibly N-isobutyrylbaleabuxidienine F), C₃₀H₅₀N₂O₃; alkaloid C (new), C₂₆H₄₁NO, with a C=C-C=O grouping and a N(CH₃)₂ group; alkaloid D, C₃₀H₅₀N₂O₄; alkaloid E (new), C₂₇H₅₀N₂O₃; alkaloid F (possibly identical with cyclomicrophylline B), C₂₇H₄₆N₂O₂; and alkaloid G (new), C₂₇H₄₆N₂O₃.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 1, pp. 26–28, 1969     

Thermal characterization of new complexes of Zn(II) and Cd(II) with some bipyridine isomers and propionates

New mixed ligand complexes of the following stoichiometric formulae: M(2-bpy)₂(RCOO)₂·nH₂O, M(4-bpy)(RCOO)₂·H₂O and M(2,4’-bpy)₂(RCOO)₂·H₂O (where M(II)=Zn, Cd; 2-bpy=2,2’-bipyridine, 4-bpy=4,4′-bipyridine, 2,4′-bpy=2,4′-bipyridine; R=C₂H₅; n=2 or 4) were prepared in pure solid-state. These complexes were characterized by chemical and elemental analysis, IR and conductivity studies. Thermal behaviour of compounds was studied by means of DTA, DTG, TG techniques under static conditions in air. The final products of pyrolysis of Cd(II) and Zn(II) compounds were metal oxides MO. A coupled TG/MS system was used to analyse of principal volatile products of thermal decomposition or fragmentation of Zn(4-bpy)(RCOO)2·H2O under dynamic air and argon atmosphere. The principal species correspond to: C⁺, CH⁺, CH₃ ⁺, C₂H₂ ⁺, HCN⁺, C₂H₅ ⁺ or CHO⁺, CH₂O⁺ or NO⁺, CO₂ ⁺, ¹³C¹⁶O₂ ⁺ and ¹²C¹⁶O¹⁸O⁺ and others; additionally CO⁺ in argon atmosphere.     

Synthesis,structural characterization,and in vitro antimicrobial properties of salicylate and pyrazoline complexes of bismuth(III)

Displacement reactions of dichlorobismuth(III)pyrazolinates with oxygen donors such as sodium salicylate and acetate in 1?:?1 and 1?:?2 molar ratio in refluxing anhydrous benzene yields (C₁₂H₁₅N₂OX)Bi(C₆H₄O₃), (CH₃COO)BiCl(C₁₅H₁₂N₂OX), and (CH₃COO)₂Bi(C₁₅H₁₂N₂OX) [C₁₂H₁₅N₂OX?=?3(2′-hydroxyphenyl)-5-(4-X-substituted phenyl) pyrazoline X?=?H in 1,5,9, CH₃ in 2,6,10, OCH₃ in 3,7,11, and Cl in 4,8,12, respectively, (C₆H₄O₃)?=?salicylate and (CH₃COO)?=?acetate]. Newly synthesized derivatives are brown solids, soluble in organic solvents like benzene, chloroform, and acetone. The compounds have been characterized by elemental analyses (C, H, N, Cl, and Bi), molecular weight measurements, and spectral (IR, ¹H NMR, ¹³C NMR) studies. The (C₁₂H₁₅N₂OX) and (C₆H₄O₃) are bidentate while (CH₃COO) is monodentate to bismuth(III), leading to a distorted trigonal bipyramidal structure. The complexes were screened against different bacteria and fungi showing potential antibacterial and antifungal activities.     

Proton and carbon nuclear magnetic resonance study on some n- and o-acyl derivatives of monohydroxypyridines

Comparative study on the proton and carbon NMR spectra for a series of $\text{N}$- and $\text{O}$-acyl substituted monohydroxypyridines (C₅H₄NO$\text{R}$: $\text{R}$=-H, -CHO, -COCH₃, -COC(CH₃)₃, -COCF₃, -COC₆H₅, -SO₂CH₃, -SO₂C₆H₄CH₃ is reported. p]Characteristic ¹H, ¹³ NMR and IR spectral features allow simple and unambiguous distinction between the isomeric $\text{N}$- and/or $\text{O}$-acyl-derivatives of 2-, 3- and 4-hydroxypyridines, so that both forms can clearly be identified when tautomeric equilibria occur, since the tautomerism rate is slow on the NMR time scale