bluuebunny/crossref_metadata_2025 huggingface dataset:
Neue Gemischtligandenkomplexe mit Perthiocarboxylaten
Authors: Piotroschke J. , Strauch P. , Abram S. , Abram U.
Published: January 2005

Lösungen von O‐Methyl‐1,1‐dithiooxalat (i‐dtoMe) und Metall(II)‐chloriden (NiII, PdII) im molaren Verhältnis 2:1 reagieren mit equimolaren Mengen gleichkerniger Bischelate anderer 1,1‐ und 1,2‐Dithioverbindungen L (L = i‐mnt, Etxan, dto)

Abkürzungen: i‐mnt: 1,1‐Dicyanoethen‐2,2‐dithiolat Etxan: Ethylxanthogenat dto: 1,2‐Dithiooxalat i‐dtoMe: O‐Methyl‐1,1‐dithiooxalat ptoMe: O‐Methyl‐1,1‐perthiooxalat

unter Ligandenaustausch zu Gemischtligandenkomplexen M(ptoMe)L bei spontaner Umwandlung des 1,1‐Dithiooxalates zum entsprechenden Perthioliganden (ptoMe) durch Schwefelinsertion. Tetraphenylphosphonium (1,1‐dicyanoethen‐2,2‐dithiolato)(O‐methyl‐1,1‐perthiooxalato)niccolat(II), Ph4P[Ni(i‐mnt)(ptoMe)], kristallisiert in der monoklinen Raumgruppe P21/n mit a = 11,019(2) Å, b = 13,648(3) Å, c = 20,882(3) Å, β = 92,565(7)°. Die Bildung des Perthioliganden konnte mittels 13C‐NMR bestätigt werden.
Neue ternäre Selenide der Lanthanide durch Reduktion der Sesquiselenide
Authors: Heinze Thomas , Urland Werner
Published: January 2005

Die Verbindungen MLn2Se3 (M = Na, Ln = LaSm) und MLn8Se12 (M = Na, Ca; Ln = LaSm) wurden durch Reduktion der entsprechenden Lanthanidsesquiselenide mit Natrium bzw. Calcium erstmals dargestellt. Weitere Selenide MLa8Se12 (M = Sr, Eu) konnten analog erhalten werden. Die dargestellten Verbindungen wurden analytisch und röntgenographisch charakterisiert. Zur Bestimmung der elektronischen Struktur dieser Verbindungen wurden Bandstrukturrechnungen und magnetische Messungen durchgeführt.
Silanolato‐Komplexe von Titan und Zirconium. Die Kristallstrukturen von Cp2TiCl(OSiPh3) und Cp2ZrCl(OSiPh3)
Authors: von Gudenberg Dorothea Wolff , Kang Hak‐Chul , Massa Werner , Dehnicke Kurt , Maichle‐Mössmer Cäcilia , Strähle Joachim
Published: January 2005

Die Titelverbindungen werden aus Cp2MCl2 (M = Ti, Zr) und Triphenylsilanol in Diethylether in Gegenwart von Piperidin hergestellt. Sie bilden nur wenig feuchtigkeits‐empfindliche orange (Ti) bzw. farblose Kristallnadeln (Zr), die wir kristallographisch charakterisiert haben.

Cp2TiCl(OSiPh3): Raumgruppe P21/n, Z = 4, Strukturlösung mit 3961 unabhängigen, beobachteten Reflexen, R = 0,057. Gitterkonstanten bei −50°C: a = 1029,6; b = 1719,3; c = 1388,9 pm, β = 100,69°. Die Verbindung bildet monomere Moleküle mit Abständen TiO von 184,2 pm, SiO von 161,5 pm und einem TiOSi‐Bindungswinkel von 164,5°.

Cp2ZrCl(OSiPh3): Raumgruppe P3, Z = 18, Strukturlösung mit 2799 unabhängigen, beobachteten Reflexen, R = 0,047. Gitterkonstanten bei −20°C: a = b = 3518; c = 1058,3 pm. Die Struktur enthält drei symmetrieunabhängige monomere Moleküle, die sich nur wenig voneinander unterscheiden. Die Abstände ZrO betragen im Mittel 196,4 pm, SiO im Mittel 162,1 pm und die Bindungswinkel ZrOSi im Mittel 173,7°.
Ein Beitrag zur Reaktivität von (η5‐C5Me5)(CO)2FeP(SiMe3)2 gegenüber P‐Chlormethylenphosphanen
Authors: Weber Lothar , Kirchhoff Ralf , Stammler Hans‐Georg , Neumann Beate
Published: January 2005

Die Reaktion von (η5‐C5Me5)(CO)2FeP(SiMe3)2 (2) mit drei Äquivalenten des P‐Chlorphosphaalkens ClP = C(SiMe3)2 (3a) lieferte das 3‐Methandiyl‐1,3,5,6‐tetra‐phosphabicyclo[3.1.0]hex‐2‐en (η5‐C5Me5)(CO)2Fe
equation image
(6a). Demgegenüber reagiert 2 mit zwei Äquivalenten an ClPC(Ph)SiMe3 (3b) zu der thermolabilen Verbindung (η5‐C5Me5)(CO)2FeP[PC(Ph)SiMe3]2 (4b), die sich bei der Behandlung mit überschüssigen 3b zersetzt. 4b wird auch bei der Umsetzung von (η5‐C5Me5)(CO)2FeP(SiMe3)PC(SiMe3)2 (1a) mit zwei Äquivalenten 3b erhalten.
Übergangsmetall‐substituierte Acylphosphane und Phosphaalkene. 22 [1] Insertionen von Hexafluoraceton in die PX‐Bindung von Metallophosphanen des Typs (η5‐C5Me5)(CO)2MPX2 (M = Fe, Ru; X = Me3Si, Cl). Strukturbestimmung von (η5‐C5Me5)(CO)2FeP(SiMe3)C(CF3)2(OSiMe3)
Authors: Weber L. , Misiak H. , Stammler H.‐G. , Neumann B.
Published: January 2005

Die Reaktion der Metallophosphane (η5‐C5Me5)(CO)2MP(SiMe3)2 (1a: M = Fe; 1b: M = Ru) mit Hexafluoraceton (HFA) liefert die Komplexe (η5‐C5Me5) · (CO)2MP(SiMe3)C(CF3)2(OSiMe3) (2a, b) Eliminierungsversuche von Hexamethyldisiloxan unter Ausbildung eines Metallophosphaalkens scheiterten. Bei der säurekatalysierten Hydrolyse von 2a entsteht die Verbindung (η5‐C5Me5)(CO)2FeP(H)C(CF3)2(OSiMe3) (3). Hexafluoraceton und (η5‐C5Me5)(CO)2FePCl2 (4) reagieren zum Metallophosphan (η5‐C5Me5)(CO)2FeP(Cl)OC(CF3)2Cl (5). Konstitution und Konfiguration der Verbindungen (2–5) wurden durch Elementaranalysen und spektroskopische Daten (IR, 1H‐, 13C, 19F‐, 29Si‐, 31P‐NMR sowie MS) ermittelt. Von 2a wurde zudem eine Einkristall‐Röntgenstrukturanalyse durchgeführt.
Beiträge zum thermischen Verhalten und zur Kristallchemie wasserfreier Phosphate. XI. Darstellung und Kristallstruktur einer triklinen Modifikation von GeP2O7
Authors: Kaiser U. , Glaum R.
Published: January 2005

Durch Hydrolyse von GeCl4 in konz. H3PO4 entstand eine neue Modifikation von GeP2O7 als mikrokristallines Pulver, das durch chemischen Transport (950 → 850°C, Transportmittel: Cl2; p = 0,1 atm (298 K) in Form stark lichtbrechender Prismen mit Kantenlängen bis zu 0,7 mm kristallisiert wurde. Die Kristallstrukturbestimmung [Raumgr.: P1; Z = 2; a = 7,730(1) Å; b = 6,724(1) Å; c = 4,6543(8) Å; α = 105,39(1)°; β = 92,81(1)°; γ = 91,49(1)°; 1 358 symmetrie‐unabhängige I0; 94 Parameter; konventioneller Gütefaktor R1 = 3,1%] zeigt CN = 6 für Ge (regelmäßiges Oktaeder: d̄Ge1O = 1,86 Å; d̄Ge2O = 1,85 Å) und P2O7‐Gruppen (d̄P1O = 1,53 Å; d̄P2O = 1,53 Å) mit ∠ (POP) = 126,5°. Jedes O ist zweifach mit P oder mit einem P und einem Ge koordiniert. Diese Modifikation von GeP2O7 zeigt enge Verwandtschaft zur Kristallstruktur von PtP2O7 und zum [MoP2O7]‐Wirtsgitter von Na0,3MoP2O7, unterscheidet sich aber deutlich von den kubischen Strukturen zahlreicher anderer Metall(IV)‐diphosphate.
1,1′‐Disubstituierte Titanocen‐dithiolen‐Chelate des Typs (η5‐Me3EC5H4)2Ti(S2C2R2) (E = C, Si, Ge)
Authors: Plinke Bettina , Köpf Hartmut
Published: January 2005

Die Reaktion der Titanocen‐dichloride (η5‐Me3EC5H4)2TiCl2 (E = C, 1a; E = Si, 1b; E = Ge, 1c) mit den 1,2‐Dithiolaten (NaS)2C2H2, (NaS)2C2(CN)2 oder (LiS)2C6H3Me‐4 ergab die neuen Titanocen‐dithiolen‐Chelate (η5Me3EC5H4)2Ti(S2C2H2) (2a–c), (η5‐Me3EC5H4)2Ti[S2C2(CN)2] (3a–c) und (η5‐Me3EC5H4)2Ti(S2C6H3Me‐4) (4a–c). Sie wurden durch 1H‐NMR‐, IR‐ und Massen‐Spektroskopie charakterisiert und mit den unsubstituierten η5‐C5H5‐Analoga 2d, 3d und 4d verglichen. Für 2a–c, 3a–d und 4a–c wurden die Aktivierungs‐energien der Chelatringinversion in Lösung aus temperatur‐abhängig aufgenommenen 1H‐NMR‐Spektren abgeschätzt.
Oxo‐ und Thiotantal(V)‐Verbindungen: Synthese von TaOX3 und TaSX3 (X = OR, SR)
Authors: Preuss F. , Lambing G. , Müller‐Becker S.
Published: January 2005

TaO(OR)3 [R = tC4H9, Mes* (2)], TaO(SR)3 [R = tC4H9, p‐Tolyl], TaS(OR)3 [R = tC4H9, Mes* (6)] und TaS(SR)3[ R = tC4H9, p‐Tolyl] werden dargestellt durch Reaktion von TaOCl3 und TaSCl3 mit LiOR oder LiSR. Die Umsetzung von TaCl5 mit überschüssigem LiOMes* führt zu den Chlorotantal(V)‐Verbindungen TaCl3(OMes*)2 und TaCl2(OMes*)3 (10). Darüber hinaus wird die Synthese von TaCl2(nC4H9)(OMes*)2 (11), Ta(Sp‐Tolyl)5 und TaCl2(OEt)3 · C5H5N beschrieben. 2, 6, 10 und 11 zersetzen sich in benzolischer Lösung oder beim Erhitzen i. Vak. unter Abspaltung von 2,4,6‐Tri‐tert‐butyl‐phenol bzw. n‐Butan und Bildung von cyclometallierten Tantal(V)‐Verbindungen mit dem zweizähnigen Liganden OC6H2tBu2CMe2CH2. Die Kristallstruktur von TaCl2(OEt)3 wurde bestimmt; im zweikernigen Komplex sind die Tantalatome über zwei Ethoxo‐Liganden verbrückt.
Die Kristallstruktur des tBu2PPP(Br)tBu2
Authors: Borrmann H. , Kovacs I. , Fritz G.
Published: January 2005

tBu2PPP(Br)tBu2 1 kristallisiert monoklin in der Raumgruppe P21/c mit a = 2 888,9(3), b = 972,16(10), c = 1 534,04(14) pm, β = 105,129(8)° und 8 Formeleinheiten in der Elementarzelle. Die beiden unabhängigen P3‐Einheiten in 1 sind gewinkelt (105,77° bzw. 105,98°). Die PP‐Abstände entsprechen mit 220,4 pm einer Einfachbindung bzw. mit 207,9 pm einer Doppelbindung.
Tetraarylester der μ‐Imidodiphosphorsäure und ihre Thioderivate — Strukturuntersuchungen
Authors: Herrmann Eckhard , Nouaman Moein , Žák Zdirad , Großmann Gisbert , Ohms Gisela
Published: January 2005

Neue O,O′,O″,O‴‐Tetratolyl‐ und Diphenylditolyl‐ester der μ‐Imido‐diphosphorsäure und ihres Monothio‐ und Dithioderivates wurden synthetisiert, in ihren Eigenschaften mit den bekannten Phenylestern verglichen und 1H‐, 13C‐ und 31P‐NMR‐spektroskopisch untersucht. Die Kristall‐ und Molekülstrukturen des O,O′,O″,O‴‐Tetrakis‐(2‐methyl‐phenyl)‐μ‐imido‐diphosphats, 1b, sowie der entsprechenden ortho‐, meta‐, und para‐Tolylester der μ‐Imido‐monothiodiphosphorsäure (2b, 2c, 2d) konnten gelöst werden. Alle Verbindungen bilden über NH…︁O‐Wasserstoffbrücken Dimere, die auch in unpolaren Lösungsmitteln erhalten bleiben. Die Bindungsabstände um die P‐Atome nehmen mit sinkender Elektronegativität der Substituenten zu. Durch 13C{1H, 31P}‐ Tripelresonanzexperimente wurde das Vorzeichen der 2JPNP‐ Kopplungskonstanten für einige Verbindungen bestimmt. Bei Substitution von Phosphoryl‐ durch Thiophosphorylgruppen werden diese Konstanten negativer.
Effect of carbonate incorporation on the structural and superconducting properties of the double chain compound Y2Ba4Cu7O15−x
Authors: Krüger Ch. , Schwer H. , Karpinski J. , Conder K. , Kaldis E. , Rossel C. , Maciejewski M.
Published: January 2005

Structural investigations on powder samples of Y2Ba4Cu7O15–x with different carbonate content have been performed. Powder x‐ray Rietveld refinements showed the remarkable influence of carbonate incorporation on the lattice parameters. Most important is the decrease of Tc with increasing carbonate content. We assign these effects to an incorporation of the carbonate ion into the crystal lattice, copper vacancies at the Cu(1) position and a possible misorientation of the copper oxygen single chains. No change of the structure (e. g. superstructure) could be found.
Salze von Halogenophosphorsäuren XIX [1] Über die Bildung und den Nachweis stabiler Intermediate bei der Reaktion von Fluorid mit Phosphoroxidchlorid
Authors: Kant M. , Meisel M.
Published: January 2005

Bei der Reaktion von POCl3 mit Fluoriden tertiärer Ammoniumbasen in nichtwäßriger, basischer Lösung werden als Zwischenprodukte auf dem Weg zum [PF6]− das Heptafluorodiphosphat [F2P(O)OPF5]− sowie die Oxofluorophosphate [OPF5]2− und [OPF4]− gebildet und NMR‐spektroskopisch charakterisiert.
Chemischer Transport von Cr2O3 mit CrI3/I2 – Experimente und Modellrechnungen zur Beteiligung von CrOI2,g
Authors: Nocker K. , Gruehn R.
Published: January 2005

Cr2O3 wandert bei Zugabe von Iod (z. B. 0,1 mmol/ml) und CrI3 im Temperaturgradienten 1 000°C→900°C über das bislang unbekannte Oxidiodid CrOI2 und CrI2 (Gl. 1), wobei CrI4 als Transportmittel anzusehen ist

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Mit kleineren Transportmitteldichten (D(I2) ⩽ 0,016 mmol/ml) sowie weniger hoher Temperatur (z. B. T̄ = 850°C) gewinnt der Einfluß von H2O und demgemäß ein Transport von Cr2O3 über die endothermen Gleichgewichte Gl. (2) bis (4) an Bedeutung.

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Der Wasserstoff in Gl. (4) besitzt in den Modellrechnungen aufgrund des Zerfalls von HI eine positive Löslichkeitsdifferenz und sollte damit als Transportmittel nicht in Frage kommen. Unter den genannten Bedingungen ist diese Reaktion aufgrund der Größenordnung der Kp‐Werte ebenfalls zu berücksichtigen. Thermodynamische Modellrechnungen ermöglichen, die Bildungsenthalpie des Oxidiodids auf ΔBH°298(CrOI2,g) = −51,4 kcal/mol mit einem geringeren Fehler als ± 5 kcal/mol einzugrenzen.

Im System Cr2O3/I2 war ohne Zusatz von CrI3 kein Transporteffekt zu beobachten.
Li10Si2PbIIO10 = Li20[(SiO4)4(OPbO2PbO)] — Das erste „gemischte”︁ Silicat‐Plumbat(II)
Authors: Brandes R. , Hoppe R.
Published: January 2005

Farblose Kristalle von Li10Si2PbO10 entstanden beim Tempern inniger Gemenge von LiPb, Li2O2 und „SiO2”︁ (aus Duranglas) in Ag‐Bömbchen (650°C; 60 d). Die Kristallstruktur wurde aufgeklärt (Vierkreisdiffraktometerdaten, MoK, 1 474 Io(hkl), R = 4,2%, Rw = 2,8%, Parameter siehe Text). Das Silicat‐Plumbat kristallisiert monoklin (Raumgruppe C2/m; I. T. No. 12) mit a = 2 985,1(4); b = 610,6(1); c = 512,8(1) pm; β = 99,70(9) (Vierkreisdaten), Z = 4.

Ferner werden der Madelunganteil der Gitterenergie (MAPLE), Effektive Koordinationszahlen (ECoN), die Mittleren Fiktiven Ionenradien (MEFIR) sowie die Ladungsverteilung (CHARDI) berechnet.
Das erste Titanat mit „Stuffed Pyrgoms”︁: RbNa3Li12[TiO4]4 = RbNa3Li8{Li[TiO4]}4
Authors: Weiß C. , Hoppe R.
Published: January 2005

Durch Tempern eines innigen Gemenges der binären Oxide Rb2O, Na2O, Li2O und TiO2 [Rb:Na:Li:Ti = 1,1:3,1:12,5:4,0; 780°C, 41 d] wurde RbNa3Li8{Li[TiO4]}4 in Form von farblosen Plättchen erhalten. Das erste Titanat mit „stuffed pyrgoms”︁ ist isotyp zu RbNa3Li8{Li[SiO4]}4, CsKNa2Li8{Li[SiO4]}4 und CsKNaLi9{Li[SiO4]}4 [2]. Die Verbindung kristallisiert tetragonal I4/m mit den Gitterkonstanten a = 1 125,8(1) pm und c = 652,4(1) pm (Guinier‐Simon‐Daten, Z = 2). Die Struktur wurde mit Vierkreisdiffraktometerdaten (Siemens AED2, 657Io(hkl), MoK) aufgeklärt und führte zu den Residualwerten R = 3,7% und Rw = 3,1% (weitere Daten siehe Text). Der Madelunganteil der Gitterenergie (MAPLE), Effektive Koordinationszahlen (ECoN), Mittlere Fiktive Ionenradien (MEFIR) sowie die Ladungsverteilung (CHARDI) werden berechnet und diskutiert.
Polyol‐Metall‐Komplexe. X. Blei(II)‐meso‐oxolan‐3,4‐diolat(2−)‐Monohydrat – ein polymeres Blei‐alkoxid aus wäßriger Lösung
Authors: Klüfers Peter , Schuhmacher Jörg
Published: January 2005

Blei(II)‐ und meso‐Oxolan‐3,4‐diolat(2−)‐Ionen bauen in den farblosen Kristallen von Pb(C4H6O3) · H2O (P21/c, a = 569,8(3), b = 607,6(4), c = 1856,9(9) pm, β = 89,90(4)°, V = 642,9(6) · 106 pm3, Z = 4) ein kettenförmiges Koordinationspolymer auf, in dem PbII von vier verbrückenden Alkoxid‐O‐Atomen koordiniert ist (mittlerer Abstand: 234,5 pm); ungefähr 100 pm weiter entfernt koordinieren zwei ebenfalls verbrückende Wasser‐O‐Atome.
Crystal and Molecular Structure of Bis(η5‐methylcyclopentadienyl)titana(IV)‐cyclohexasulfane Ti(η5‐C5H4CH3)2S5
Authors: Klouras Nikolaos , Demakopoulos Ioannis , Terzis Aris , Raptopoulou Caterina P.
Published: January 2005

The crystal and molecular structure of Ti(n5‐C5H4CH3)2S5has been determined by X‐ray diffraction studies. The substance crystallizes in the monoclinic crystal system [a = 6.8642(5), b = 16.507(1), c = 13.074(1) Å, β = 82.407(3)°, space group P21/n, Z = 4]. The geometry about the titanium atom is a distorted tetrahedron, with a (centroid)‐Ti‐(centroid) angle of 131.29° and a STiS angle of 93.38°. The six‐membered ring TiS5 has a cyclohexane‐like chair configuration. The structural results are compared to those for similar type titanium complexes.
Darstellung und Kristallstruktur von Cobalt(II)‐Hexaoxodiphosphat(PP)(4−)‐dodecahydrat, Co2P2O6 · 12 H2O
Authors: Hagen S. , Jansen M.
Published: January 2005

Co2P2O6 · 12 H2O entsteht bei oxidativer Ringspaltung an cyclo‐Hexaphosphaten(III) in ammoniakalisch ethanolischer Lösung. Die Kristallstruktur wurde auf der Basis von Vierkreisdiffraktometerdaten (4018 gemessene Reflexe) gelöst (1 898 unabhängige Reflexe): Raumgruppe Pbam (No. 55); a = 6,710(2), b = 12,196(2), c = 10,073(3) Å, V = 825,3(1) Å3; Z = 2; R = 0,060. Die Anionen P2O64− mit der Lagesymmetrie C2h sind über Cobalt zu Ketten verknüpft. Je zwei Cobaltionen bilden mit je vier Wassermolekülen und zwei terminalen Sauerstoffatomen des P2O64− verzerrte, kantenverknüpfte Oktaederpaare aus. Deren gemeinsame Kanten werden durch Sauerstoffatome der P2O6‐Gruppen gebildet.
Zur solvensfreien Darstellung von Tetramethylammoniumsalzen: Synthese und Charakterisierung von [N(CH3)4]2[C2O4], [N(CH3)4][CO3(CH3)], [N(CH3)4][NO2], [N(CH3)4][CO2H] und [N(CH3)4][O2C(CH2)2CO2(CH3)]
Authors: Albert B. , Jansen M.
Published: January 2005

Es wird ein allgemeines Verfahren zur Synthese von Tetramethylammoniumsalzen vorgestellt. Bisher wurden auf dem Wege der solvensfreien Umsetzung von Trimethylamin mit verschiedenen Methylverbindungen unter milden Bedingungen die Tetramethylammoniumsalze [N(CH3)4]2[C2O4] (kubisch; a = 1 114,8(3) pm), [N(CH3)4][CO3CH3] (P21/n; a = 813,64(3), b = 953,36(3), c = 1 131,3(4) pm, β = 90,03(1)°), [N(CH3)4][NO2] (Pmmn; a = 821,2(4), b = 746,5(3), c = 551,5(2) pm), [N(CH3)4][CO2H] (Pmmn; a = 792,8(7), b = 791,7(3), c = 563,3(4) pm) und [N(CH3)4][O2C(CH2)2CO2CH3] (P21; a = 731,1(2), b = 826,4(3), c = 1 025,2(3) pm, β = 110,1(1)°) kristallin dargestellt. Die schwingungsspektroskopische und röntgenographische Charakterisierung aller aufgeführten Tetramethylammoniumsalze sowie die Kristallstrukturen von [N(CH3)4][CO3CH3] und [N(CH3)4][NO2] werden beschrieben.
Metallkomplexe von Phenylenbistriazeniden: Synthese und Kristallstrukturen von [Cp(CO)2M]2(1,2‐PhN3C6H4N3Ph) (M = Mo, W)
Authors: Hörner M. , Galvan J. M. , Beck J.
Published: January 2005

[Cp(CO)2M]2(1,2‐PhN3C6H4N3Ph) [(M = Mo(1), M = W(2)] entsteht bei der Reaktion von Cp(CO)3MCl mit PhN3(H)C6H4N3(H)Ph und C2H5ONa in einem THF/Ethanol‐Gemisch. 1 kristallisiert aus Toluol in Form dunkelroter Kristalle (triklin, P1, a = 1 499,3(9) pm, b = 1 734,0(7) pm, c = 1 852,8(8) pm, α = 66,84(3)°, β = 78,25(4)°, γ = 77,19(4)°). Die Elementarzelle enthält vier Komplexe, von denen jeweils zwei symmetrisch unabhängig sind, und acht Solvensmoleküle. 2 kristallisiert aus THF in Form gelber, solvensfreier Kristalle (triklin, P1, a = 979,0(5) pm, b = 1 152,8(5) pm, c = 1 475,8(5) pm, α = 98,26(4)°, β = 104,93(4)°, γ = 101,03(4)°, Z = 2). 1 und 2 sind diskrete Molekülkomplexe, in denen ein 1,2‐Bis(phenyltriazenido)phenyl‐Ligand, (PhN3C6H4N3Ph)2−, jeweils zwei Cp(CO)2M‐Einheiten über die N‐Atome N1 und N3 der beiden N3‐Ketten chelatisierend koordiniert. Durch die räumlich anspruchsvollen Cp(CO)2M‐Einheiten weicht der Phenylenbistriazenido‐Ligand stark von der in anderen Metallkomplexen angetroffenen Planarität ab.
Halogenometallate von Übergangselementen mit Kationen stickstoffhaltiger heterocyclischer Basen. I. Die Kristallstrukturen von 1,4‐Dimethylpiperazinium‐tetrachlorocobaltat(II) und ‐zinkat(II), (dmpipzH2)[MIICl4] (M = Co, Zn)
Authors: Feist Michael , Trojanov Sergej , Kemnitz Erhard
Published: January 2005

Die Verbindungen (dmpipzH2)[MIICl4] kristallisieren monoklin in der Raumgruppe P21/m mit a = 6,133(1), b = 14,306(1), c = 6,902(1) Å, β = 90,54(2)°, Z = 2 für M = Co und mit a = 6,141(1), b = 14,282(1), c = 6,907(1) Å, β = 90,60(2)°, Z = 2 für M = Zn. In den Strukturen liegen Tetraeder [MCl4]2− und zentrosymmetrische (dmpipzH2)2+‐Kationen in Sesselform vor. Es werden gabelförmige Wasserstoffbrückenbindungen des Typs NH …︁ Cl zu zwei Chloridionen gebildet. Zwei kurze Abstände C …︁ Cl werden als CH …︁ Cl‐Wasserstoffbrückenbindungen gedeutet.
Trifluoroethylene Sultone: Structure and Chemistry
Authors: Braden Dale A. , Gard Gary L. , Oberhammer Heinz
Published: January 2005

The gas phase structure of trifluoroethylene sultone, (1) (3,4,4‐trifluoro‐1,2‐oxathietane‐2,2‐dioxide) was determined by gas electron diffraction, and the four‐membered ring was found to be planar. The following ring parameters (ra distances and ∠α angles with 3σ uncertainties) were derived in the electron diffraction analysis: CO = 1.41 Å (ass.), CC = 1.541(18) Å, SO = 1.652(5) Å, SC = 1.822(8) Å, SCC = 86.2(15)°, CCO = 97.1(28)°, COS = 97.5(21)°, and OSC = 79.1(8)°. New spectral data (IR, NMR) of 1, its acyclic isomer FSO2CFHC(O)F (2), and the related anhydride, FSO2OSO2CFHC(O)F (3), are reported. New esters containing the fluorosulfonyl function, FSO2CFHC(O)OCH2CF3 (4), FSO2CFHC(O)OCH2CH = CH2 (5), and (FSO2CFHC(O)OCH2CHCH2)n (6) have been prepared and characterized.
Mechanistic aspects of the thermal stabilisation of PVC by organotin compounds
Authors: Burley Joseph William
Published: January 2005

When subjected to heat and mechanical shear PVC decomposes via the elimination of HCl. This process is controlled most efficiently by the use of organotin stabilisers. This review outlines the basic degradation/stabilisation mechanisms which are involved in these processes. The organotin compounds of most commercial significance receive particular attention. Model compound studies which highlight potential stabilisation mechanisms are discussed but emphasis is placed on in‐situ studies which are much more realistic. Finally the phenomenon of synergism is discussed with reference to conventional alkyltin and the more novel estertin compounds.
Applications of fast atom bombardment mass spectrometry (FAB MS) to organometallic and coordination chemistry
Authors: Bruce Michael I , Liddell Michael J
Published: January 2005

This article describes the technique of fast atom bombardment mass spectrometry (FAB MS) and its applications to the analysis of organometallic and coordination complexes. Sections on ion generation and matrices are followed by a Periodic Group‐based review of FAB MS results obtained from Transition Metal and Main Group compounds, organometallic cluster carbonyls and their derivatives, and salts of poly‐oxo‐anions. The literature has been surveyed from 1981 to approximately mid‐1986.
Studies on the phytotoxic effects of some organotin(IV) compounds on the germination of the mung bean seed, Phaseolus aureus
Authors: Balabaskaran S , Tilakavati K , Das V G Kumar
Published: January 2005

A selected range of organotin(IV) compounds of formula RxSnX4‐x (x = 2 or 3; R = alkyl, cycloalkyl or aryl), as well as the adducts, (p‐ZC6H4)3SnCl. Ph3PO (Z = H, Me) were examined in vivo for their phytotoxic effects relative to the more powerful s‐triazine herbicides against the mung bean seed, Phaseolus aureus. Phytotoxicity was assessed in terms of changes in (a) weights of primary leaves, (b) weights of cotyledons, (c) seedling heights and (d) root morphology. The triorganotin compounds were more phytotoxic than the diorganotins, and within the R3Sn structural class, inhibitory potency was greater for alkyltins than for aryltins. Decreasing the alkyl chain lengths or placing electrondonating substituents on the aromatic rings increased the phytotoxicity. A significant phytotoxic effect, comparable with that of Ph3SnCl, was manifested by tricyclohexyltin chloride, in marked contrast to the well‐known low phytotoxicity of tricyclohexyltin hydroxide.

Using Ph3SnCl as the model compound, it was further demonstrated that the total chlorophyll content decreased with increasing concentration of Ph3SnCl, but the ration of chlorophyll a to chlorophyll b was constant. It was also found that tin uptake in the seedlings was directly proportional to Ph3SnCl test concentrations; the magnesium and iron levels in the treated seedlings, however, were unchanged relative to the control.
The fate of tributyltin toxicants in neoprene‐based elastomeric antifouling coatings: 119mSn Mössbauer, 119Sn NMR and chemical studies
Authors: Allen David W , Brooks John S , Bailey Stephen , Taylor Brian F
Published: January 2005

The fate of a series of tributyltin toxicants on incorporation into cured neoprene elastomers has been studied by 119mSn Mössbauer and 119Sn NMR spectroscopic techniques, together with supporting chemical derivatization techniques. It is shown that all of the toxicants undergo chemical change during the curing process, being converted into tributyltin chloride, together with (in some cases) tributyltin stearate and a small amount of dibutyltin distearate. Possible interactions between the organotin agents and other components of the elastomer, e.g. carbon black filler, and cure accelerators such as tetramethylthiuram disulphide, have also been investigated.
Analysis of tributyltin in estuarine sediments and oyster tissue, Crassostrea virginica
Authors: Rice C D , Espourteille F A , Huggett R J
Published: January 2005

An analytical method to determine tributyltin (TBT) in oyster tissue, Crassostrea virginica, and estuarine sediments is described. Recoveries of TBT from oysters range from 86 to 102% when samples are fortified at concentrations ranging from 22 to 890 μg kg−1 (wet weight); recoveries from sediment range from 92 to 105% for samples fortified from 20 to 500 μg kg−1 (dry weight).

Feral oysters and natural sediments were analysed and shown to be contaminated with TBT. Oysters collected near a marina contained concentrations as high as 1.5 mg kg−1 (wet weight).
Silane compounds in hot‐water pipe and cable technology
Authors: Gale G M
Published: January 2005

The problems of technique and equipment used in the crosslinking of polyethylene polymer are discussed. The practice of organosilicon chemistry for crosslinking of polyethylene chains is also considered. The use of a Cavity Transfer Mixer (CTM) for control of silane‐based crosslinking is described and the properties of the resultant polymers are tested. Use of this crosslinking method via the CTM produces polyethylene with improved hot‐water characteristics.
Bis(tributyltin) oxide as a wood preservative: Its chemical nature in timber
Authors: Blunden S J , Hill R
Published: January 2005

Tributyltin compounds have been used for many years as wood preservatives. This study has provided, for the first time, an explanation for the previously reported dealkylation and/or volatilization of the tributyltin species in, and from, timber. Thus 119Sn NMR studies have shown that, on impregnation into timber, bis(tributyltin) oxide, (Bu3Sn)2O, is rapidly converted to other tributyltin species, Bu3SnOX, and that these subsequently undergo disproportionation to Bu4Sn and Bu2Sn(OX)2 compounds. We have additionally demonstrated that Bu4Sn, so produced, is not persistent in timber and is lost by volatilization. Since the rate of disproportionation of the Bu3SnOX species should be dependent upon the nature of the X group, it should be possible to affect significantly, if not to stop, this process by the use of alternative tributyltin fungicides, e.g. tributyltin methanesulphonate. However, tributyltin fungicides have been used successfully in wood preservation for at least 25 years. Therefore, it must be concluded that, even after disproportionation in timber, in service, sufficient preservative action is retained to prevent decay of wood under the conditions of natural exposure.
Characterization and studies of electroactive properties of an organometallic polymer of iron‐phthalocyanine
Authors: Nalwa Hari S
Published: January 2005

An iron‐phthalocyanine polymer has been characterized by infrared spectroscopy, X‐ray diffraction and Mössbauer spectroscopy. The electrical properties of resistivity, dielectric constant and the thermally stimulated depolarization effect have been investigated in the temperature range 30–240°C. The depolarization of thermoelectret shows two current peaks at about 176°C and 200°C. The unpolarized sample also displays a pyroelectric current on heating, indicating the possibility of ferroelectric polarization. A temperature‐dependent measurement of the dielectric constant exhibits a dielectric maximum around 180°C which is likely due to electret current peaks. The results have been compared with a monomer of iron‐phthalocyanine and interpretations are made in terms of the highly delocalized π‐electron system of the phthalocyanine macrocycle being further extended by polymerization.
Arsenate metabolism in aquatic plants
Authors: Benson A A , Katayama M , Knowles F C
Published: January 2005

Of the several types of arsenic metabolic pathways in algae and aquatic higher plants, production of arsenoribosides is predominant and most interesting. Insertion of the ribosyl or adenosyl moiety by transfer from S‐adenosylmethioninine or possibly from adenosylcobalamin is the critical biochemical step which, as yet, has not been experimentally demonstrated. Oceanic or other environmental arsenate (AsO43−), absorbed in the plant's quest for phosphate, is fixed by reaction with ATP to yield the phosphoric arsenic anhydride APAs, a short‐lived but reducible intermediate which is converted to arsenic(III). The Hill Reaction, or thioredoxin reductase, reduces it to an arsine oxide (HAsO) or arsonous acid [HAs(OH)2] depending upon the water content of its environment. This readily diffusible reagent avidly attacks sulfhydryl groups of proteins to produce arsonous thioesters. The Sargassum group of algae appears to process arsenate no further than this. The reduced arsenic may be freed from its sulfur bondage by reaction with 2,3‐dimercaptopropan‐1‐ol (BAL) or dithiothreitol. In experiments with Sargassum fluitans and Sargassum natans no arsenoribosides were observed. Only protein‐bound arsenic was observed. It could be liberated by trituration with dithiothreitol to produce the cyclic arsonous dithioester.

Most diatoms, dinoflagellates and macroalgae as well as freshwater higher plants release such protein‐bound arsenic as a result of sequential methylation and adenosylation. Ultimately the products are trialkylarsine oxides, innocuous substances which are slowly or not‐at‐all metabolized by herbivorous animals or bacteria. Fortunately mammals and most animals also excrete the arsenoribosides readily, unchanged. Arsenic metabolism by a cyanobacterium, Phormidium sp., was described by Matsuto et al. (Comp. Biochem. Physiol., 1984, 78c:377) as involving two modes of arsenate fixation, reduction, and excretion. We have extended those experiments with Phormidium persicinum. We have analyzed algae from 2‐ and 7‐day culture in radioarsenate media. The arsenic products included 80% of arsenolipid, similar if not identical to that formed in the brown algae. The water‐soluble products were in low concentration. Insoluble, protein‐bound arsonous thioesters accounted for 8% of the fixed arsenic. The mechanism of arsenic depuration in Phormidium appears to be primarily lipid‐mediated.
A study of dimethyltin(IV)‐L‐cysteinate in aqueous solution
Authors: Silvestri Arturo , Duca Dario , Huber Friedo
Published: January 2005

The in vivo activity of some R2Sn‐L‐cysteinate complexes (R = Me, Et, n‐Bu) against murine P‐388 leukaemia has been tested. Only the Et2Sn(IV) complex showed a marginal positive effect. Trigonal bipyramidal tin environments with two carbon (R) atoms and the sulfur atom in the equatorial plane and oxygen (carboxylate) and nitrogen (NH2) in apical positions have been proposed for the solid compexes (R = Me, Et, n‐Bu, Ph) on the basis of experimental Mössbauer parameters and infrared (IR) data. Aqueous solutions of the Me2SnL‐cysteinate have been studied by IR, 1H NMR and 119Sn Mössbauer spectroscopy (in frozen solution) at different pH values to identify the Me2Sn(IV) species present. At pH > 2 the dimethyltin aquocation is complexed by the ionized sulfhydryl group of L‐cysteine to form a five‐coordinated species. With increasing pH values, NH3+ is deprotonated and a chelate is proposed with both the sulfhydryl and the amino group bonded to tin, one water molecule or (at still higher pH values) one hydroxyl ion occupying the fifth coordination site of a trigonal bipyramid around tin. Finally at pH > 10 the NH2 group is substituted by a hydroxyl ion.
Organometallics in the nearshore marine environment of Australia
Authors: Maher W A , Batley G E
Published: January 2005

This review draws together published information on the occurrence and biogeochemical cycling of selenium, arsenic and tin in the nearshore marine environment of Australia. The selenium content of marine organisms is well documented but little information is available on the selenium content of waters and sediments. The speciation of selenium in organisms, water and sediments is unknown although it appears that selenium is associated with proteins. The occurrence and speciation of arsenic in marine organisms has been extensively studied, with arsonobetaine being isolated as the probable end‐product of arsenic metabolism in marine food chains. However, organisms can produce other organoarsenic compounds, e.g. trimethylarsine oxide, which may be metabolized to toxic end‐products. Little is known about the occurrence and speciation of arsenic in waters and sediments. Arsenic(V) is dominant in oxygenated waters, with appreciable quantities of arsenic(III) in some deoxygenated waters.

There are few data for tin in water, sediments or organisms and no data on naturally occurring tin species. Tributyltin has been measured in water, sediment and organisms from areas affected by boating activity.
CVD of metal organic and other rare‐earth compounds
Authors: Deacon Glen B , MacKinnon Peter , Dickson Ron S , Pain Geoff N , West Bruce O
Published: January 2005

Three major applications have been found for rare‐earth compounds in Metal Organic Chemical Vapour Depostion (MOCVD) or Chemical Vapour Deposition (CVD). Yttrium 2,2,6,6‐tetramethyl‐3,5‐heptanedionates and 6,6,7,7,8,8,8‐heptafluoro‐2,2‐dimethyl‐3,5‐octanedionates have been used in conjunction with barium and copper(II) β‐diketonates to deposit YBa2Cu3O7−δ as superconducting thin films. Rare‐earth fluorides and chlorides have been used for CFD doping of rare earths into MOCVD‐deposited ZnS, whilst yttrium chloride has been used, with barium iodide and copper(I) chloride, to produce YBa2Cu3O7−δ superconducting material by CVD. Lanthanoid (Ln) tris(cyclopentadienyl) compounds, Ln(C5H5)3 or Ln(C5H4Me)3, have been used for doping of rare earths into 13–15 (III–V) semiconductors. Their volatility, structure/volatility relationships, and preparations are discussed. Possible alternative reagents and problems to be faced in doping 12–16 (II–VI) semiconductors are also considered.
Interactions of organotins with biological systems
Authors: Musmeci M Teresa , Madonia Grazia , Giudice M Teresa Lo , Silvestri Arturo , Ruisi Giuseppe , Barbieri Renato
Published: January 2005

The bonding and structure in the environments of tin atoms in organotin‐biological molecules has been investigated by 119Sn Mössbauer spectroscopy, mainly through the rationalization of the nuclear quadrupole splitting parameter by pointcharge model approaches.

Organotin moieties R2SnIV and R3SnIV (R = Me, nBu, Ph) generally assume trigonal‐bipyramidal type configurations in membranes of human erythrocytes, when incubated with whole erythrocytes and erythrocyte ghosts at the level of micromolar (μmol dm−3) organotin per mg of membrane protein. Corresponding structures are assumed by Me2SnIV and Me3SnIV in the cytoplasm. Ethanolic Me2SnCl2 yielded distorted trans‐octahedral species when reacted with ghost cells. These configurations may in principle originate through coordination of the metal by donor nitrogen or oxygen atoms from the cell constituents, such as protein side chains and related component molecules, carbohydrate fragments, and phospholipids, according to data from various model systems. Hydrolyzed species, such as bis(chlorodiorganotin) oxides and triorganotin hydroxides, could also occur for the n‐butyltin and phenyltin species.

The moieties Me2SnIV and Alk3SnIV (Alk = Me, Et, nBu), present as the hydrolysis products Me2Sn(OH)2 and Alk3SnOH at physiological pH in the aqueous phase (eventually coordinated by donor atoms from buffers), react with thiol groups of model molecules, as well as of feline and rat hemoglobin, forming tetrahedral or trigonalbipyramidal tin sites characterized by covalent SnS bonds (C2SnS, C2SnS2 and C3SnS skeletons); tin atoms are eventually further coordinated by nitrogen donors from amino acid fragments or from buffers, as well as by hydroxyl oxygen.
Crystal structure and in vitro antitumor activity of bis(dicyclohexylammonium) bis(2‐sulfobenzoato)dibutylstannate
Authors: Ng Seik Weng , Das V G Kumar , Gielen Marcel
Published: January 2005

An X‐ray structure determination is presented for bis(dicyclohexylammonium) bis(2‐sulfobenzato)dibutylstannate, and its antitumor properties against mammary and colon carcinoma cell lines are reported.
Methylmercury(II) complexes with 2‐mercaptopyridinecarboxylic acids
Authors: Garcia M E , Thunus L , Monteagudo J C G , Fonseca J M L , Casas J S , Sordo J
Published: January 2005

The stability constants of the complexes [MeHgL]−(H2L = 2‐mercaptopyridine‐3‐carboxylic acid, 2‐mercaptopyridine‐4‐carboxylic acid, 2‐mercaptopyridine‐5‐carboxylic acid and 2‐mercaptopyridine‐6‐carboxylic acid) have been obtained by differential pulse polarography. The values of log β1 are in the range 14.14–14.96 at 20°C and ionic strength 0.1 mol dm−3. The complexes MeHgHL have been isolated and characterized by chemical analysis and mass and IR spectrometry.
Synthesis of polyphenylacetylene free‐standing films in the presence of rhodium–imidazole catalysts
Authors: Russo M V , Lucci G , Furlani A , Camust A , Marsich N
Published: January 2005

A new dinuclear rhodium(I) complex [Rh2(cod)2(imH)2im]PF6 (I) has been synthesized and characterized. The complex is unstable in solution where it undergoes modifications leading to insoluble oligomers. However, it exhibits high catalytic activity towards polymerization of phenylacetylene (PPA) films can be obtained under mild reaction conditions. As‐grown PPA films are stable and soluble. Two different types of morphologies were found: one exhbits a cell‐like structure with microfibrils inside the cell and the other a dense enamel‐like smooth surface.
The interaction of organotins with native DNA
Authors: Piro Vincezo , Di Simone Francesco , Madonia Grazia , Silvestri Arturo , Giuliani Anna M. , Ruisi Giuseppe , Barbieri Renato
Published: January 2005

The compounds R2SnCl2 and R3SnCl (RMe, Et, nBu, nOct, Ph, in ethanol solution) as well as the aqueous species [Me2Sn(OH2)n]2+ and [Me3Sn(OH2)2]+, react with aqueous native DNA, yielding solid phases. According to the pointcharge model treatment of the 119Sn Mössbauer parameter nuclear quadrupole splitting, trans‐octahedral R2Sn(O2PXY)2, and trigonalbipyramidal R3Sn(O2PXY), (RMe, Et, nBu), would occur in the pellets, the tin atoms being coordinated by phosphodiester groups of the nucleic acid. The precipitates from Ph2SnIV would consist of the DNA complex as well as of the Ph2SnIV distannoxane obtained by hydrolysis of the reactant, whilst nOct2SnCl2, nOct3SnCl and Ph3SnCl would mainly yield stannoxanes and hydroxides. The water‐soluble hydrolyzed species [Me2Sn(OH)(OH2)n]+, Me2Sn(OH)2 and Me3Sn(OH)(OH2) do not show any interaction with native DNA, although they are possibly coordinated by phosphate oxygen atoms in model aqueous systems, in the presence of excess ligand.

These trends have been rationalized by QSAR approach (Quantitative Structure‐Activity Relationships) in terms of electronic factors related to tin‐oxygen (phosphate) Coulomb interactions, as well as the lipophilicity of R in the RnSnIV moieties.
Electrochemical methods for the determination of total arsenic and arsenic compounds
Authors: Greschonig Herbert , Irgolic Kurt J
Published: January 2005

The determination of total arsenic and of arsenic compounds in biological and inorganic samples is a task frequently encountered by analysts. Several elecrochemical methods have been developed for the determination of total arsenic (generally after mineralization of the sample), arsenite, arsenate, methylarsonic acid and dimethylarsinic acid. The electrochemical behavior of several other organic arsenic compounds was also studied. This paper reviews these electrochemical methods, their application to environmental samples, and the problems encountered in the electrochemical determination of arsenic and arsenic compounds.
Organometallic complexes with biological molecules. I. Diorganotin(IV)chloro protoporphyrin IX complexes: Solid‐state and solution‐phase characterization
Authors: Pellerito Lorenzo , Pellerito Alessandro , Maggio Francesco , Beltramini Mariano , Salvato Benedetto , Ricchelli Fernanda
Published: January 2005

Protoporphyrin IX (H4PPIX) complexes of diorganotin(IV)chloro moieties with formula (R2SnCl)2H2PPIX (RMe, Bu and Ph) have been obtained and their solid‐state and solution‐phase configurations have been studied through spectroscopic investigations.

Coordination of the side‐chain carboxylates of H4PPIX to R2Sn(IV)Cl moieties, with bridging carboxylate (COO−) has been inferred by comparison of the free and coordinated H4PPIX IR spectra, while the occurrence of a five‐coordinated tin(IV) atom in a cis‐R2 trigonal bipyramidal structure has been deduced, for all of the synthesized complexes, by rationalization of the nuclear quadrupole splitting parameters, according to the point‐charge model formalism. Fanally, the solution‐phase spectral features of (R2SnCl)2−H2PPIX are in agreement with the monomeric character of the protoporphyrin IX, under the experimental conditions used.
Organometallic complexes in ascidian embryonic development: II. Effects on different stages and larvae
Authors: Mansueto Caterina , Valvo Mario Lo , Pellerito Lorenzo , Girasolo M Assunta
Published: January 2005

The effects of the organometallic compounds Bu2Sn‐D‐(−;)sorbitol, Bu2Sn‐D‐(+)glucose, Bu2Sn‐D‐(−)fructose and Bu2Sn‐D‐(+)glyceraldehyde were tested in vivo on different stages of Ascidian development, larval movement and metamorphosis. Organotin(IV) complexes are organometallic compounds widely used as industrial biocides, antifouling agents and agricultural fungicides and are toxic to a range of organisms. Two‐cell stage embryos, if incubated for one hour in the organotin (IV) solutions, stopped the cleavage, which was restored when they were transferred into normal sea water. The gastrula stage was seriously affected in 10−4mol dm−3 solutions of the above‐mentioned complexes: 85% of the embryos were anomalous neurulae with open neural folds, 5% were twisted larvae. The gastrulae, when incubated for 1 h in 10−5mol dm−3 solutions, developed twisted larvae in ovular envelopes and immobile larvae with twisted tails. Larvae treated with 10−4mol dm−3 and 10−5 mol dm−3 Bu2Sn‐D‐(−)sorbitol, Bu2Sn‐D‐(+)glucose and Bu2Sn‐D‐(+)glyceraldehyde solutions stopped swimming, did not metamorphose and afterwards underwent cytolysis. An initial hyperactivity of circular movements, followed by immobility, was observed in the larvae incubated in Bu2Sn‐D‐(−;)fructose.
Di‐n‐butyltin and diethyltin monofluorobenzoates: Synthesis, spectroscopic characterization and in vitro antitumor activity
Authors: Gielen Marcel , Khloufi Abdelaziz El , Biesemans Monique , Willem Rudolph
Published: January 2005

The di‐n‐butyltin(IV) and diethyltin(IV) fluorobenzoates [FC6H4COO]2SnR2 and (FC6H4COOR2Sn)2O have been synthesized and characterized spectroscopically. Their in vitro antitumor activity against two human tumor cell lines, MCF‐7, a mammary tumor, and WiDr, a colon carcinoma, as well as against the NCI cell panel, is satisfactory.
N‐tributyltin mesylimide—a new water‐soluble fungicide
Authors: Shcherbakov Vladislav I , Frolovaa Svetlana M
Published: January 2005

In addition to the known water‐soluble tributyltin compounds, N‐tributyltin mesylimide [Bu3SnN‐(SO2Me2)2] was prepared and proposed as a fungicide for water‐based preservative formulations. The aqueous solubility of the new compound is in the range of 11.0–11.4% w/w at 25 °C and its activity towards moulds (Aspergillus niger) is near that for tributyltin oxide. The compound has an average toxicity (LD50=740 mg kg−1).
Laser chemical synthesis of clusters and ultrafine particles using organometallics
Authors: Chaiken Joseph
Published: January 2005

Gas‐phase synthesis of clusters and ultrafine particles using lasers and organometallics is reviewed. The general field of laser chemistry is introduced in the context of using organometallics as reactants. Examples of particle and cluster synthesis in flowing gases and in bulk gases, and during laser chemical vapor deposition, are given. A brief introduction to the general field of random irreversible fractal coagulation provides a basis for describing how powders, clusters and ultrafine particles are synthesized. References to applications and characterization methods are given.
Diorganotin 2‐fluorocinnamates and 4‐fluorophenylacetates: Synthesis, characterization and in vitro antitumour activity
Authors: Gielen Marcel , Khloufi Abdelaziz El , Biesemans Monique , Kayser François , Willem Rudolph
Published: January 2005

The synthesis and characterization by spectroscopy of several new di‐n‐butyltin and diethyltin 2‐fluorocinnamates and 4‐fluorophenylacetates are described. In vitro tests on two human tumour cell lines, MCF‐7, a mammary tumour, and WiDr, a colon carcinoma, showed that two of these compounds are more active than cisplatin. Other in vitro tests performed by the NCI, USA on a panel of human tumour cell line show that one of them, bis[di‐n‐butyl(2‐fluorophenylacetato)tin] oxide, is characterized by statistically significant D, DTGI and D sensitivities, but non‐significant DH and MGDH selectivities, whereas the analogous 2‐fluorocinnamate shows no such significant values.
Contributions to the synthesis of some ferrocene‐containing antibiotics
Authors: Scutaru D , Tataru Lucia , Mazilu I , Vata M , Lixandru Tatiana , Simionescu Cr
Published: January 2005

This Review discusses the synthesis and characterization by our Group of new antibiotics belonging to the class of penicillins, cephalosporins and rifamycins with ferrocenyl and 1, 1′‐ferrocenilene residues in the molecule.

As reactants for 6‐aminopenicillanic acid (6‐APA) and 7‐aminocephalosporanic acid (7‐ACA) the following were used: 1, 1‐bis(chlorocarbonyl)ferrocene, ferrocenyl sulfochloride, 1, 1′‐ferrocenylenedisulfochloride and thioglycolic acids S‐modified with ferrocene. In the synthesis of rifamycins, the hydrazides of the thioglycolic acids, S‐modified with ferrocene, were employed as nucleophilic agents. The synthesized intermediates were characterized by elemental analysis, TLC, IR, UV and 1H NMR spectra. The characterization of new antibiotics was made by TLC, IR and UV spectral analysis.

Biological activity was tested on Gram‐negative and Gram‐positive bacteria. Good activity is reported towards Gram‐positive bacteria in the case of derivatives containing residues of thioglycolic acid S‐modified with ferrocene, the antibacterial activity being similar to that of amoxicillin, carbenicillin and cephalothin. All compounds are inactive towards Gram‐negative bacteria.
Synthesis and spectroscopic characterization of R3SnIV derivatives of N‐acetyldipeptides
Authors: Huber Friedo , Vornefeld Michael , Ruisi Giuseppe , Barbieri Renato
Published: January 2005

Triorganotin(IV) derivatives of N‐acetyldipeptides R3SnAcDip; RMe, Et, n‐Bu, n‐Oct, Cy or Ph (HAcDipN‐acetylglycylglycine and N‐acetylglycylvaline; RMe, n‐Bu, Cy, HAcDipN‐acetylglycylalanine) were obtained by neutralization of R3SnOH and HAcDip. The complexes were studied by means of 119Sn Mössbauer, IR and 1H, 13C and 119Sn NMR spectroscopy. The CSnC bond angles have been inferred by rationalization of Mössbauer nuclear quadrupole splittings as well as from NMR coupling constants. Correlations of Mössbauer isomer shifts with partial atomic charges on tin atoms have been determined: Polymeric trigonal bipyramidal structures, with near‐planar R3Sn units and axial carboxylate (unidentate) and CO amide donor groups are inferred for all the compounds in the solid state, except for Cy3SnAcGlyVal for which a tetrahedral structure is proposed. In solution the complexes are monomeric; in methanol a solvent molecule is coordinated to tin which then is still in a trigonal bipyramidal environment.