Jochen Ellermann

Aufbau einer propionateinheit aus ethylen, wasser und einer carbonylgruppe: Darstellung und charakterisierung von propionatokomplexen mit dem [Ru(CO)2(μ-OOCC2H5)]2-strukturelement

Abstract The reaction of Ru3(CO)12 with ethylene and water under pressure results in the formation of a propionato complex containing the [Ru(CO)2(μ-OOCC2H5)]2 unit. From 13C and 18O isotope labelling studies, the μ-OOC carboxyl moieties of this species were shown to arise from a carbonyl ligand of the ruthenium carbonyl employed and the oxygen atom of the water present in the reaction mixture. From the tetrahydrofuran solution, a solid of composition [Ru(CO)2(μ-OOCC2H5)]2. 0.3C4H8O (1) was isolated. Infrared and Raman studies suggest 1 to consist of binuclear Ru2 units, which are connected in the solid phase by ruthenium—oxygen interactions. In solution, however, the Ru2 units are stabilized by two coordinating solvent molecules; in the case of acetonitrile, the binuclear adduct could be isolated as the crystalline material [Ru(CO)2(μ-OOCC2H5)]2·2CH3CN (2).

Chemie polyfunktioneller moleküle: LXXVII. Das reaktionsverhalten von bis(diphenylphosphino)amin gegenüber di-μ-chloro-bis[dicarbonylrhodium(I)]☆

Abstract This paper describes the direct synthesis of the A-frame complex Rh 2 (μ-CO)(μ-Ph 2 PNHPPh 2 ) 2 Cl 2 ·CH 3 OH·O(C 2 H 5 ) 2 (IV′) from [Rh(μ-Cl)(CO) 2 ] 2 and Ph 2 -PNHPPh 2 (I). The intermediates formed, [Rh 2 (μ-CO)(μ-Cl)(μPh 2 PNHPPh 2 ) 2 (CO) 2 Cl·0.5O (C 2 H 5 ) 2 (Va), Rh 2 (μ-CO)(μ-Cl)(μPh 2 PNHPPh 2 ) 2 (CO)(Cl)·0.5O(C 2 H 5 ) 2 (VI), and the by-product [Rh(CO)(Cl)(Ph 2 PNHPPh 2 )·(1–2) CH 3 OH] n (VII), were isolated and characterized. Compound IV′ reacts with CO to yield Va, which undergoes a metathesis reaction with NaBPh 4 or NH 4 PF 6 , to give [Rh 2 (μ-CO)(μ-Cl)(μ-Ph 2 PNHPPh 2 ) 2 (CO) 2 ]BPh 4 ·CH 3 OH (Vb) and [Rh 2 (μ-CO)(μ-Cl)(μ-Ph 2 PNOPPh 2 ) 2 (CO) 2 ]PF 6 (Vc). The reaction of [Rh(μ-Cl)(CO) 2 ] 2 with I in a molar ratio of 3 4 , yields (Rh 2 (μ-CO)(μ-Cl)-(μ-Ph 2 PNHPPh 2 ) 2 (CO) 2 ][Rh(CO) 2 Cl 2 ]·2CH 3 OH (Vd). The reaction of [Rh(μ-Cl)(CO) 2 ] 2 with I in a closed tube (molar ratio 1 2 ) yields [Rh 2 (μ-CO)(μ-Cl) (μ-Ph 2 PNHPPh 2 ) 2 (CO) 2 ]Cl·CH 3 OH (Va′). The compound [Rh 2 (gm-Cl)-(μ-Ph 2 PNHPPh 2 ) 2 (CO) 2 ]BPh 4 ·CH 3 OH (VIII) is obtained from Vb in methanolic solution with CO elimination. From a solution of VIII in CH 2 Cl 2 , [Rh 2 (μ-Cl)(μ-CH 2 Cl 2 ) (μ-Ph 2 PNHPPh 2 ) 2 (CO) 2 ]BPh 4 -O(C 2 H 5 ) 2 (IX) precipitates on adding diethyl ether. Red IX in methanolic solution converts back to the yellow VIII. The structures of the new compounds are determined on the basis of 31 P{ 1 H} NMR, 1 H NMR, IR, ESR and MS spectroscopic and conductometric data.

Komplexchemie polyfunktioneller liganden : XLIII. Schwingungsspektroskopische untersuchungen an metalltetracarbonyl-derivaten ditertiärer phosphine

Abstract Using infrared spectra the v (CO) and in some cases also the δ(MCO), v (MC) and v (MP) modes of the metal carbonyl complexes cis -M(CO) 4 (LL) (M = Cr, Mo, W; LL = (C 6 H 5 ) 2 P(CH 2 ) n P(C 6 H 5 ) 2 ; n = 1, 2) have already been investigated and results published. The CO force constants are also described in the literature. The compounds mentioned above, together with the complexes cis -M(CO) 4 (C 6 H 5 ) 2 P(CH 2 ) 3 P(C 6 H 5 ) 2 ,were reinvestigated by infrared spectroscopy and for the first time by Raman spectroscopy. Likewise the influences of solvents on the v (CO) frequences were studied. The results obtained show the need to revise the assignments of the v (MC) and v (MP) modes.

Die komplexchemie polyfunktioneller liganden : XXVIII. Über die selektive spaltung von arsenphenyl-bindungen mit jodwasserstoff in nichtwässrigen systemen☆

Abstract The phenylalkyl arsines (CH 3 ) 2 AsC 6 H 5 , CH 3 As(C 6 H 5 ) 2 , C 2 H 5 As(C 6 H 5 ) 2 , (CH 2 ) n [As(C 6 H 5 ) 2 ] 2 ( n = 1, 2), and C[CH 2 As(C 6 H 5 ) 2 ] 4 react with liquid or gaseous HI in nonaqueous solvents by selective cleavage of the arsenicphenyl bonds yielding (CH 3 ) 2 AsI, CH 3 AsI 2 , C 2 H 5 AsI 2 , (CH 2 ) n (AsI 2 ) 2 and C(CH 2 AsI 2 ) 4 . The latter forms the tetradentate ligand C[CH 2 As(CH 3 ) 2 ] 4 with CH 3 MgI. The electron impact mass spectra of these compounds show clear fragmentation patterns resulting mainly from the formation of fragments with AsAs bonds or (As) n clusters ( n = 3, 4). From CH 3 AsI 2 and C 2 H 5 AsI 2 the iodine-free cycloarsines (AsCH 3 ) 3 , (AsC 2 H 5 ) 3 , (AsC 2 H 5 ) 4 , As 3 (C 2 H 5 ) 2 CH 3 and As 4 (C 2 H 5 ) 3 CH 3 are formed by thermal secondary reactions in the high temperature inlet systems of the mass spectrometer. The fragmentations of the cycloarsines and the other compounds are discussed. The infrared spectral absorptions of all the alkyl iodoarsines can be completely assigned in the range of 4000 – 250 cm −1 . The IR data of C 2 H 5 AsI 2 indicate the existence of trans and gauche rotational isomers.

Chemie polyfunktioneller moleküle: LXXIX. Kristall- und molekülstruktur von μ,-carbonyl-μ-chloro-di[μ,-bis(diphenylphosphino)-amin-p,P′]-bis[carbonyl-rhodium(I)]chlorid-methanol (1/1)☆

Abstract The molecular and crystal structure of the compound [Rh2(μ-CO)(μ-Cl)(μ-Ph2PNHPPh2)2(CO)2]Cl·CH3OH (1/1) (II) have been investigated in order to obtain confirmation of the complicated hydrogen bridge linkage system, deduced earlier from vibrational spectroscopy. Crystals of II are triclinic, space group P 1 , with a 1680.6(1.1), b 1380.6(5), c 1190.5(1.1) pm, α 96.30(3), γ 96.00(7), γ 110.75(3)° and Z = 2. On the basis of 3258 unique reflections, the structure was refined by blocked matrix least-squares techniques to a conventional R value of 0.064. The two rhodium atoms of the cation are bridged by two nearly transoid PNP ligands. In the equatorial plane, which is not exactly perpendicular to the waved bridging ligand planes, the two metals are slightly asymmetrically bridged by a Cl and a CO ligand. A terminal CO group on each metal, one nearly colinear with the single RhRh bond (273.7 pm), the other at an angle to die metal-metal distance, completes the rhodium coordination. The geometry of the rhodium atoms can be described as a significant distorted bipyramid. The cations of II are connected together to infinite chains along the b-axis of the crystal by strong hydrogen-bridging bond systems.

Chemie polyfunktioneller moleküle: LXXVI. Metallcarbonyl-, metallnitrosylcarbonyl-und metallnitrosyl-komplexe des bis(diphenylphosphino)amins

Abstract The compound Ph 2 PN(H)PPh 2 (I) reacts under special conditions with M(CO) 6 (M  Cr, Mo), Fe(NO) 2 (CO) 2 and Co(NO)(CO) 3 to give the new complexes cis -M(CO) 2 [Ph 2 PN(H)PPh 2 ] 2 (III, IV), [Fe(NO) 2 (CO)Ph 2 P] 2 NH (V), [Fe(NO) 2 Ph 2 -PN(H)PPh 2 ] 2 (VI) and Co(NO)(CO) 2 Ph 2 PN(H)PPh 2 (VII). Compound VI can also be prepared reacting V with I. For III and IV proton NMR spectra indicate some interaction between o -protons of the phenyl rings and cis -M(CO) 2 groups. VI exists an eight-membered ring complex without a metal-metal bond. On the basis of spectroscopic data VII seems to exist in two conformers.

Chemie polyfunktioneller Moleküle: CXIII. Komplexe des Dicobaltoctacarbonyls mit den Liganden Bis(diphenylphosphino)amin und -amid

The yield of the earlier published Co2(μ-CO)2(CO)4(μ-dppa)·12 C6H6 (4·12 C6H6) [dppa = bis(diphenylphosphino)amin (1)] could now be increased from 30% to 80%. In the polar solvent tetrahydrofuran (THF) Co2CO)8 and dppa react to the ionic complex [Co(CO)(dppa)2][Co(CO)4] · 2 THF (5a · 2 THF). Metatheses of 5a · 2 THF with NaBPh4 in ethanol led to the formation of [Co(CO)(dppa)2]BPh4 (5b). Under UV irradiation 4 · 12 C6H6 and dppa gives the CO-bridging-free Co2(CO)4(μ-dppa)2 (7a). The course of the reaction was studied by infrared spectroscopy. After adding n-hexane to the THF solution of 7a the CO-bridged isomer Co2(μ-CO)2(CO)2(μ-dppa)2 (7b) precipitates. The structure of 7b was determined by X-ray crystallography. Co2+1(μ-CO) (CO)4((μ-PPh2-N-PPh2⊖)(μ-PPh2⊖) (9) was prepared from 4 · 12 C6H6, n-butyllithium and ClPPh2 in benzene. Suitable crystals for X-ray structural studies were obtained from a CH2Cl2/n-hexane mixture. The X-ray investigation showed that the Co-Co bond bridging anions [Ph2PXXXNXXXPPh2]⊖ and PPh2⊖ are in trans position to each other in 9· CH2Cl2. With the cobalt atoms they form five and three membered rings in the same plane. All compounds were characterized by 1H NMR, 13C{1H}NMR, 31P{1H} NMR and IR spectroscopy.

Über verschiedene reaktionen der co-verbrückten komplexe [Mo(CO)3Bipy]2 und [Mo(CO)3Phen]2 (Bipy=2,2′-bipyridin, Phen=1,10-phenanthrolin): II. Neue gemischte ein- und zweikernige tricarbonylkomplexe des molybdäns mit mehrzahnigen n- und P-liganden

Summary The reaction of the binuclear CO-bridged compounds [Mo(CO) 3 Q] 2 (Q = Bipy, Phen) with multidentate P-Ligands in benzene leads to the formation of mononuclear mixed ligand complexes Mo(CO) 3 QL when the P-Ligand is present in excess. [Q=Bipy, Phen; L=Ph 2 PPPh 2 , Ph 2 P(CH 2 ) n PPh 2 ( n =1–3), Ph 2 P(CH 2 ) 2 -N(C 2 H 4 ) 2 ; the reaction with L=CH 3 C(CH 2 PPh 2 ) 3 occurs only when Q=Bipy.] {fd} The reaction of 1/1 stoichiometric quantities results in binuclear complexes [Mo(CO) 3 Q] 2 L [Q=Bipy, Phen; L=Ph 2 P(CH 2 ) n PPh 2 ( n =1-3); the reaction with L=CH 3 C(CH 2 PPh 2 ) 3 occurs only when Q=Bipy]. {fd} The structures of the new compounds have been inferred on the basis of IR active ν(CO), ν(MoC) and δ(MoCO) vibrations, molecular weight determinations and chemical reactivity.

Chemistry of polyfunctional molecules—1231. Reactions of BiBr3, SbI3 and AsI3 with LiN(PPh2)2; X-ray structure of a cyclophosphazene salt containing arsenic(I)

Abstract BiBr3 or SbI3 react at 20°C with LiN(PPh2)2 (1) to give elementary Bi or Sb and the PP coupled phosphazene ligand Ph2PNPPh2PPh2NPPh2 (2). The reaction of AsI3 with 1 at room temperature formed yellow needles of the eight-membered heterocycle (3), whereas AsI3 interacted at 80°C with 1 in the molar ratio of 1:3 to give elementary arsenic and 2. Treatment of AsI3 and 1 at 20°C in a 1:2 stoichiometry yielded the seven-membered, cyclic arsenium(I) salt I·4THF (5·4THF), which was characterized by elemental analysis, conductivity, mass, IR and NMR spectroscopy and single-crystal X-ray structural analysis.

Chemie polyfunktioneller Molekäle, 130. Mitt. [1]: Rubidium- und Cäsium-bis(diphenylphosphanyl)amid – Synthesen, (18-Krone-6)-Komplexe, Spaltprodukte, Kristallstrukturen und Festkörper-NMR-Spektren

Summary. The metalation of bis(diphenylphosphanyl)amine, HN(PPh2)2 (5), with RbOtBu in the presence of N,N,N′,N′′,N′′-pentamethyldiethylenetriamine (PMDTA (3)) in toluene surprisingly affords the nearly PMDTA free RbN(PPh2)2 (6a). Recrystallization of 6a from tetrahydrofuran (THF) yields RbN(PPh2)2ċ0.5 THF (6b). Compounds 6a, b crystallize in thin needles; however, these are not suitable for X-ray structure analyses. The reactions of 5 with MOtBu (M=Rb, Cs) in the presence of 18-crown-6 in toluene yield the monomeric, pale yellow rubidium and caesium complexes [Rb(18-crown-6)(N(PPh2)2)] (7) and [Cs(18-crown-6)(N(PPh2)2)] (8), respectively. Allowing to stand a solution of 8 in THF for three months at 20°C results in a cleavage product of 8. This is identified as the dimeric yellow complex [(Cs(18-crown-6))2(μ-N*P(H)Ph2)2]ċTHF (9). The source of the hydrogen atom in the bridging phosphorane iminate anion [N*P(H)Ph2]− is uncertain. Compounds 7–9 are structurally characterized by X-ray analyses. These reveal that [N(PPh2)2]− acts as P-ligating chelate in 7, whereas it coordinates the Cs+ as N-donor as well as η2 C-donor with one phenyl group in 8. No phosphorus coordination is observed in 8. The two caesium cations in 9 are two-fold N-bridged by [N*P(H)Ph2]−. The coordination sphere of each caesium atom is completed by a 18-crown-6 ligand. The solid state 13C NMR spectrum of 8 reveals dynamic phenomena (rotation of the 18-crown-6 ligand). In the solid state 31P spectrum of 8, 31P, 31P–J-coupling is observed between the chemically non-equivalent phosphorus sites (J=390 Hz).