Spacer-verbrückte Bis-, Tris- und Tetrakis(ferrocenyl)-1,3-Diketone

Hydrocarbon-bridged Metal Complexes. XLVII. Bis-, Tris- und Tetrakis(ferrocenyl)-1,3-Diketones Claisen condensation of the enolate from acetylferrocene with diethyloxalate, 1,8-octanedicarboxylic dimethyl ester, fumaroyl dichloride, the chlorides of terephthalic acid and of 1,3,5-benzenetricarboxylic acid, tetramethyl-1,2,4,5-benzene tetracarboxylate and with 3,6-di-t-butyl-9,9′-dimethyl-xanthene-1,8-dicarboxylic dimethyl ester gives the corresponding bis-, tris- and tetrakis(ferrocenyl)-1,3-diketones 2 – 8 . Their oxidation potentials were measured by cyclovoltammetry. Diferrocenoyl methane exists in the crystal as the keto-enol tautomer.     

Die Darstellung von Bis-(8-hydroxy-2-methyl-5-chinolyl)-methan (I) und seine Eigenschaften als Komplexbildner

Ohne Zusammenfassung     

[(1,3-Dioxolan-2-yliden)methyl]phosphonate und -phosphinate als (einfache) Synthone in der Heterocyclensynthese

[(1,3-Dioxolan-2-ylidene)methyl]phosphonates and -phosphinates as [simple] Synthons in Heterocyclic Synthesis The readily available [(1,3-dioxolane-2-ylidene)methyl]phosphonates and -phosphinates 2a–f (Scheme 1) can be transformed with amines to aliphatic ketene N,O-and N,N-acetales (see Scheme 2, 2a → 3–7 ). Alkanediamines yield with 2a–f the imidazolidines 8a–f and the hexahydropyrimidines 9a–d (Scheme 3). the oxazolidine derivatives 10a–e and the thiazolidine 11 are accessible under special reaction conditions starting from 2a, b (Scheme 4). Hydrazines react with the CN-group-containing ketene O,O-acetals 2a–c to the pyrazoles 12a–g , whereof 12a, d, e can be cyclized to pyrazolo[1,5-a]pyrimidines 13a–d (Scheme 5). Amidines as starting materials transform 2a–c in an analogous way to the pyrimidine derivatives 14a–c (Scheme 6).     

Darstellung und Eigenschaften von Phosphanboranen polyfunktioneller Phosphanliganden; Kristallstrukturen des Bis(boranatodiphenylphosphonio)methans und des Tetrakis[(boranatodiphenylphosphonio)methyl]methans

Preparation and Properties of Phosphane-Boranes Derived from Polyfunctional Phosphanes; Crystal Structures of Bis(boranatodiphenylphosphonio)methane and Tetrakis[(boranato-diphenylphosphonio)methyl]methane Bis(boranatodiphenylphosphonio)methane has been prepared in pure form from Ph₂PCH₂PPh₂ (dppm) via two synthetic routes and its crystal structure determined. The molecule adopts a conformation very similar to that of the parent dppm ligand, which reflects the influences of the repulsive charges in the functional groups. Analogous phosphine-boranes were obtained from 1,1,1-tris(diphenylphosphinomethyl)ethane and tetrakis(diphenylphosphinomethyl)methane. The crystal structure has also been determined for the tetra-borylated derivative of the latter. A highly symmetrical arrangement has been found which corresponds to a relaxed conformation of the four dipolar groups. From C(CH₂PPh₂)₄ and H₂BBr · SMe₂ an ionic, spirobicyclic Product was obtained, which resembles the monocyclic analogues previously described in its Properties and spectroscopic data.     

Organische Phosphorverbindungen 42. Einige Reaktionen von Bis-(dialkoxyphosphonyl-methyl)-O-alkylphosphinaten und Tris-(dialkoxyphosphonyl-methyl)-phosphinoxiden [1]

The metallation of alkyl bis-(dialkyloxyphosphonyl-methyl)-phosphinates (I) and tris-(dialkyloxyphosphonyl-methyl)-phosphine oxides (II) proceeds quantitatively with Na, K, or NaH in inert organic solvents. Alkylation of these metallated derivatives is effected with alkyl halides. In addition to the mono-alkylated products, the di-alkylated and the non-alkylated products are formed also. The ester groups of II can be replaced by aryl groups by reaction with Grignard reagents to produce the corresponding tetratertiary phosphine oxides. Reduction of II with LiAlH₄ results in complete rupture of the molecule and produces only the cleavage products PH₃ and CH₃PH₂. Chlorination of the ester groups of I and II does not lead to uniform products. Concomitant with the chlorination of the ester groups, a cleavage reaction has been observed which produces as the main product Cl₂CHP(O)Cl₂. The anhydride of the hexa-acid of II is readily obtained either by reaction of this acid with (CH₃CO)₂O or by reaction of II with (PhCO)₂O. The titration behaviour and the high m. p. indicate an adamantane-like structure for the anhydride. Halogenation of the bridging PCH₂P groups of I and II is achieved by reaction with aqueous alkaline hypohalite at ambient temperature. This halogenation is accompanied by partial cleavage, and analytically pure samples could not be isolated.     

Pyridinderivate als Komplexbildner IX Die Stabilitätskonstanten von Komplexen mit (a) 2-aminomethyl-pyridin, (b) 6-methyl-2-aminomethyl-pyridin, (c) 2-pyridylhydrazin, (d) 2,2′-dipyridylamin und (e) 1-(α-pyridylmethylen)-2-(α′-pyridyl)-hydrazin

The complex formation of the ligands given in the title has been investigated using potentiometric measurements at ionic strength 0,1 and 20°C. The results are discussed in comparison with the known values and with those of similar ligands.     

Ti7Cl16 und Ti7Br16 sowie weitere Untersuchungen mit Titanhalogeniden. Al2X6 als Komplexbildner

Ti₇Cl₁₆ and Ti₇Br₁₆ and Further Investigations with Titanium Halides. Al₂X₆ as a Complex Forming Agent TiCl_3,s can be transported with Al₂Cl₆ via TiAlCl_6,g in a temperature gradient. The equilibrium of this reaction was studied by mass spectroscopy. There is no indication of the existence of a TiAl₂Cl₉ molecule as assumed in the literature. β-TiBr₃ was prepared from the elements in the presence of the transporting agent Al₂Br_6,g. The transport of TiCl₂ with Al₂Cl_6,g involves, as an important step, the disproportionation which is favoured by the reaction of Ti with the glass wall. If the disproportionation is made impossible by addition of Ti the novel compound Ti₇Cl₁₆ is obtained. Independent of Ti₇Cl₁₆, a phase TiCl_{(2 + x)} with a broad range of homogeneity exists. The compound Ti₇Br₁₆, being isostructural with Ti₇Cl₁₆, was also prepared. Results of magnetic measurements and observations on the thermal decomposition of the compounds are reported.     

Zur Reaktion der Lanthanoiden mit Chelatliganden Darstellung und Struktur von [(py2CH)3Gd]

On the Reaction of the Lanthanides with Chelate Ligands Synthesis and Crystal Structure of [(py₂CH)₃Gd] GdBr₃ reacts with [(py₂CH)Li] to the mononuclear complex [(py₂CH)₃Gd] 1 . The structure of 1 was characterized by X-ray single crystal structure analysis. Space group P2₁, Z = 2, a = 951.4(10) pm, b = 1369.4(10) pm, c = 1074.5(10) pm, β = 105.69(8)°. The Gd-Ion is surrounded by the six nitrogen atoms of the three chelate ligands and shows a distorted trigonal prismatic coordination. As a difference to the lithium salt of the ligand, the six-membered metalla-cycles in 1 are not planar, but show a boat conformation.     

Übergangsmetallphosphidokomplexe. VIII. Strukturuntersuchungen an Übergangsmetallphosphor-Vier- und Sechsringkomplexen. Die Strukturen von [(CO)4MnPH2]2, [(CO)4MnPH2]3 und [cpNiPH2]3

Transition Metal Phosphido Complexes. VIII. X-Ray Diffraction Studies of Transition Metal Phosphorus Four- and Six-Membered Ring Complexes. Structures of [(CO)₄MnPH₂]₂, [(CO)₄MnPH₂]₃, and [cpNiPH₂]₃ [(CO)₄MnPH₂]₂ 1 crystallizes triclinic in the space group P1 with a = 680.4 pm, b = 706.4 pm, c = 919.1 pm, α 110.5°, β = 91.92°, γ 115.65°, and Z = 1 formula unit. The molecule exhibits a centrosymmetrical structure. The bond angles within the planar four-membered (Mn? P)₂-ring are 76.1° at the Mn atoms and 103.9° at the P atoms, respectively. The average Mn? P bond distance is found to be 235.1 pm. [(CO)₄MnPH₂]₃ 2 crystallizes monoclinic in the space group P2/n with a = 905.2 pm, b = 974.8 pm, c = 1264.2 pm, β = 109.1°, and Z = 2 formula units. The framework of the six-membered (Mn? P)₃-ring can be described as having a twist boat conformation. The average endocyclic bond angles are with 89.1° at the Mn atoms and 130.1° at the P atoms, respectively, largely widened compared to 1 . The average Mn? P bond distance, which is found to be 238.5 pm, is also slightly increased compared to 1 . [cpNiPH₂]₃ 3 crystallizes rhombohedral in the space group R3. The cell constants (hexagonal setting) are a = b = 1686.1 pm, c = 561.1 pm and Z = 3 formula units. The six-membered (Ni? P)₃-ring exhibits a chair conformation. The endocyclic bond angles are with 92.3° at the Ni atoms and 124.3° at the P atoms, respectively, comparable with those of the six-membered ring compound 2 . The Ni? P bond distance is found to be 215.2 pm. The eyclopentadienyl ligands are disordered and have been refined as rigid groups.     

Über die Koordinationstendenz saurer Aminogruppen,IX. Die Kristall- und Molekülstruktur von Bis-[3-phenyl-5-pyridyl(2)-pyrazolato]-nickel(II)

The crystal and molecular structure of the diamagnetic, non-ionic- Ni(II) chelate of 3-phenyl-5-pyridyl(2)-pyrazole, [Ni(PPP)₂], are described. [Ni(PPP)₂] crystallizes in the monoclinic space group P2₁/c. The Ni? N distances (1.88 Å) are shorter and the C? C and C? N distances are smaller than expected. The molecular structure is discussed in comparison with other nickel(II) complexes with N-coordination.     

Spirocyclische Titanamide mit der Diphenylsila-titanadiazacyclobutan- Baueinheit. Kristall- und Molekülstruktur von Ti[(NSiMe3)2SiPh2]2 [1]

Durch Umsetzung der N-lithiierten Silylamine Ph₂Si(NHR)₂ mit SiCl₄ bzw. TiBr₄ wurden die spirocyclischen Amide B (R = Me, Et, i-Pr) und C (R = i-Pr, Me₃Si) dargestellt und ihre Konstitution durch Analysen, ¹H- und ²⁹Si-NMR-Spektren gesichert. Von C, R = Me₃Si, wurde an einem Einkristall eine Röntgenstrukturanalyse durchgeführt. Wichtige Strukturdaten sind: TiN 1,918(2) Å, SiN endocycl. 1,750(2) Å, exocycl. 1,738(2) Å, ? SiNTi 90,3(1)°. Spirocyclic Titanium Amides Containing the Diphenylsila-titana-diazacyclobutane Fragment. Crystal and Molecular Structure of Ti[(NSiMe₃)₂SiPh₂]₂ By reaction of the N-lithiated silylamines Ph₂Si(NHR)₂ with SiCl₄ and TiBr₄, the spirocyclic amides B (R = Me, Et, i-Pr) and C (R = i-Pr, Me₃Si) respectively have been prepared. Their constitutions have been confirmed by elemental analyses and by ¹H and ²⁹Si nmr spectroscopy. C, R = Me₃Si, has been investigated by a single crystal x-ray structure analysis. Important structural parameters are: TiN 1.918(2) Å, SiN endocycl. 1.750(2) Å, exocycl. 1.738(2) Å, ? SiNTi 90.3(1)°.     

Die Kristallstruktur des Tetrakis(di-tert.-butylphosphino)diphosphans. [(tBu)2P]2P?P[P(tBu)2]2

The Crystal Structure of Tetrakis(di-tert.-butylphosphino)diphosphane [(tBu)₂P]₂P? P[P(tBu)₂]₂ [(tBu)₂P]₂P? P[P(tBu)₂]₂ 1 obtained at ?20°C from a solution of (tBu)₂P? P=P(Br)tBu₂ forms yellow crystals (regular hexagons). 1 crystallizes monoclinic in the space group C2/c with a = 2145.6pm, b = 1137pm, c = 1696.1pm, β = 110.075° and Z = 4 formula units in the elementary cell. Due to high steric load the bond angles at the tertiary P atoms with δ = 115.7° are significantly larger than those at the primary P atoms with δ = 108.6°.     

Neue Komplexe der Lanthanoiden mit zweizähnigen Liganden. Die Strukturen von [(C17H17N2)GdBr2(thf)2] und [(C17H17N2)3Ln] (L = Sm,Gd)

New Complexes of the Lanthanoides with Bidentate Ligands. The Crystal Structures of [(C₁₇H₁₇N₂)GdBr₂(thf)₂] and [(C₁₇H₁₇N₂)₃Ln] (L = Sm, Gd) Reaction of [(AIP)Li] with GdBr₃ leads to a new mononuclear complex [(AIP)GdBr₂(thf)₂] 1 . In contrast to this with SmI₂ the compound [(AIP)₃Sm] 2 is build up. Such complexes are also formed with Gd(OR^*)₃ (R^* = O^tBu₂C₆H₃) and [(AIP)Li] in a 1:3 ratio, [(AIP)₃Gd] 3 . The structures of 1–3 were characterized by X-ray single crystal structure analysis ( 1 : space group Pna2₁ (No. 33), Z = 4, a = 1 972.7(9) pm, b = 984.7(5) pm, c = 1 425.0(8) pm, α = β = γ = 90°; 2 · 2 THF: space group C2/c (No. 15), Z = 8, a = 3 644.4(9) pm, b = 1 437.5(5) pm, c = 2 334.4(7) pm, β = 1 21.07(6)°; 3 : space group P2(1)/c (No. 14), Z = 4, a = 1 872.9(1) pm, b = 1 064.6(1) pm, c = 2 282.4(2) pm, β = 103.75(8)°).     

Nitrogen-NMR Studies on the Protonation of 2-(Aminomethyl)pyridine and Tris[(2-pyridyl)methyl]amine

¹⁴N- and ¹⁵N-NMR spectra have been recorded for 2-(aminomethyl)pyridine ( 1 ), tris[(2-pyridyl)methyl]amine ( 2 ), and some of their protonated forms. For 1 , the most basic site is the aliphatic N-atom, whereas for 2 the pyridine N-atoms are more basic, in contrast to what might be expected for a tertiary aliphatic amine.     

Derivatives of carbohydrazide, thiocarbohydrazide and diaminoguanidine as photometric analytical reagents-I 1,3-bis[(2-pyridyl)methyleneamino]thiourea and 1,3-bis[(2-pyridyl)methyleneamino]guanidine

1,3-Bis[(2-pyridyl)methyleneamino]thiourea (PMAT) and 1,3-bis[(2-pyridyl)methyleneamino]-guanidine (PMAG) have been prepared. They have been examined and characterized by infrared and ultraviolet spectroscopy. A spectrophotometric method has been used for determination of the protonation constants of the reagents. Finally, a spectrophotometric survey has been made of the reactions of various cations with PMAT and PMAG.     

Gold-Stickstoff-Heterocyclen. Synthese,Eigenschaften und Struktur von [(CH3)2AuNH2]4 und [(CH3)2AuN(CH3)2]2

Gold Nitrogen Heterocycles. Synthesis, Properties, and Structure of [(CH₃)₂AuNH₂]₄ and [(CH₃)₂AuN(CH₃)₂]₂ Dimethyl gold iodide reacts with alkali metal amides to form Au-N heterocycles. KNH₂ yields the eight-membered ring [(CH₃)₂AuNH₂]₄, whereas with LiN(CH₃)₂ the four-membered ring [(CH₃)₂AuN(CH₃)₂]₂ is obtained. The light sensitive, cyclic gold amides are stable against hydrolysis and do not react with Lewis bases. [(CH₃)₂AuN(CH₃)₂]₂ crystallizes monoclinic in the space group P2₁/c with Z = 2. The molecules exhibit the symmetry D_2h. Symmetrical amido bridges form a planar Au-N heterocyclus with distances Au-N = 214 pm.     

Die Aminoalkylierung von Chinazolinen und Chinazolonen mit Hilfe der GRIGNARD-Reaktion. 5. Mitteilung über GRIGNARD-Reaktionen mit Halogenalkyliminen [2]

Quinazoline is aminoalkylated at C(4) by 3-dimethylaminopropyl-magnesium-chloride in preparative yield to give 3 , and by oxidation 5 , just as aryl and alkyl-magnesiumbromide give 15 , 19 , and 22 . These 4-substituted quinazolines yield by further treatment with the same GRIGNARD compound by 3, 4 or 1, 2-addition 3, 4-di-hydro-quinazolines ( 12 , 16 ) and 1, 2-dihydro-quinazolines ( 13 , 17 , 20 , 23 ), the latter being formed exclusively when the 4-position in the quinazoline is occupied by bulky residues; only the later can be oxidised to give 2,4-disubstituted aromates (cf 14 , 18 , 21 , 24 ). The spectroscopic and physicochemical behaviour of the dihydro compounds and the aromatic and the aromatic compounds are discussed.