Three series of ferrocenes, derived from aminoferrocene Fc-NH2 and 1,1'-diaminoferrocene fc(NH2)2, were studied by 57Fe NMR spectroscopy. A marked decrease in 57Fe magnetic nuclear shielding with respect to ferrocene is observed if the nitrogen atom becomes part of a pi-acceptor linked to one or both cyclopentadienyl rings. In contrast, pi-donor properties of the amino group(s) affect delta57Fe to a much smaller extent. In the case of the fairly rigid structures of 1,3-diaza-2-element-[3]ferrocenophanes, a significant increase of 57Fe nuclear magnetic shielding is observed, in contrast to the corresponding [n]ferrocenophanes with n > 3. Structures of numerous of the ferrocene derivatives have been optimized for the gas phase by calculations (B3LYP/6-311 + G(d,p) level of theory), and 57Fe nuclear magnetic shieldings were calculated using these geometries. There is reasonable agreement in the trends for experimental and calculated data.

Isocyanato- (1a), 1,1'-di(isocyanato)- (2a), isothiocyanato- (1b), 1,1'-di(isothiocyanato)- (2b), isoselenocyanato- (1c) and 1,1'-di(isoselenocyanato)ferrocene (2c) were prepared and studied by H-1, C-13 and N-14 NMR spectroscopy. Isocyanatoferrocene (1a) trimerizes upon chromatography on alumina to give 3a. The molecular structures of 2c and 3a were determined by X-ray analysis, and almost undistorted ferrocene-like structures were found in both cases.

Two sterically demanding iminopyridine ligands, (2,6-diisopropylphenyl)[6-(2,4,6-triisopropylphenyl)pyridin-2-ylmeth- ylene]amine and (2,6-diisopropylphenyl)]6-(2,6-dimethylphenyl)pyridin-2-ylmethylene]amine, were prepared by a two-step process: first, condensation of 6-bromopyridine-2-carbaldehyde with an equimolecular amount of 2,6-diisopropylaniline, and second, Kumada-type coupling of in-situ-formed Grignard compounds of 1-bromo-2,6-dimethylphenyl and 1-bromo-2,4,6-triisopropylphenyl. Dichlorido complexes of the ligands were synthesized starting from FeCl2, [PdCl2(cod)], [NiCl2(dme)], and CoCl2 (cod = 1,5-cyclooctadiene, dine = dimethoxyethane). X-ray crystal structure analyses of a Fe, Pd, and Co complex were determined. Ethylene polymerization/oligomerization behavior of the dichlorido complexes after activation with methyl duminoxane or triethylaluminum was studied. Ethylene dimerization selectivity greater than 95% was observed. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

C22H30N3P, monoclinic, P121/n1 (no. 14), a = 14.0180(8) Å, b = 9.871(1) Å, c = 14.929(1) Å, β = 101.528(7)°, V = 2024.1 Å3, Z = 4, Rgt(F) = 0.055, wRref(F2) = 0.121, T = 191 K.

Ferrocenyl bridged bisaminopyridines were synthesized from 2-bromopyridine or 2-bromo-4-methylpyridine and 1,1'-diaminoferrocene using palladium catalysed aryl amination. X-ray crystal structure analysis of the two bisaminopyridines revealed the formation of dimers in the solid state. The formation of the dimers occurs via four H-bonds between the amino N-H function and the pyridine nitrogen atoms.

the ligand.The bulky phenyl substituents in the 6-position of the pyridine and at the imino Ν atom are twisted with regard to the pyridine ring with the dihedral angles of 71.8° and 93.2°, respectively.Both phenyl rings form a dihedral angle of 60.2°.The shortening of C6-N2 bond (1.27 A) indicates the imino function and the Pd-Nimino bond is slightly shorter than the Pd-Npyndine bond.Three uncoordinated dichloromethane molecules per complex molecule were found.The absolute structure was confirmed by a value of Flack parameter χ = 0.00(4).q 2 q Table 1.Data collection and handling.

It is shown that straightforward double-quantum filtered 1H MAS NMR experiments yield spectral lineshapes that permit to estimate the minimum number of 1H spins in a cluster. The approach may offer an alternative to multiple-quantum experiments for the characterisation of 1H spin clusters of moderate size. The duration of the double-quantum excitation period has to be chosen suitably, it is necessary to find a practical compromise between optimum double-quantum filtration efficiency and optimum information content of the spectral lineshapes. Some 1H MAS NMR experiments on partially deuterated maleic acid are reported as well as numerical simulations.

C26H30N2, monoclinic, C12/cl (no.15), a = 20.434(2)A, b = 8.551(1) A, c = 26.498(2)A,/? = 102.889(1)°,V= 4513.4A 3 , Z= 8, RpfF) = 0.062, wR n f(F) = 0.187, Τ =293 Κ. Source of materialFirst, 2.0 g (10.7 mmol) of 6-bromopyridine-2-carbaldehyde and 2.03 mL (1.91 g, 10.7 mmol) of 2,6-diisopropylaniline were dissolved in 30 mL of ethanol and the mixture was heated at reflux for 2 h.The solvent was removed under reduced pressure and 3.59 g (97 %) of pale yellow crystalline material (I) was obtained and used without further purification.A solution of 1.39 mL (1.93 g, 10.4 mmol) of 2-bromo-m-xylene in 30 mL THF was added to 0.30 g (12.5 mmol) magnesium turnings and the resulting suspension stirred and activated using 0.2 mL of 1,2-bromoethane.An exothermic reaction took place and an ice bath was used to cool the reaction mixture when the reaction became too vigorous.The reaction mixture was stirred at room temperature for 2 h, then filtered and the filtrate (Π) directly used.To a solution of 3.0 g (8.69 mmol) I in 30 mL of dioxane was added a suspension of 0.11 g (0.87 mmol) FeCh in 10 mL of THF.The Grignard solution Π was then slowly added to the stirred suspension.The reaction mixture was heated to 70 °C for 48 h. 100 mL of water and 80 mL of diethyl ether were added and the resulting suspension transferred to a 500 mL separating funnel.The organic phase was collected and the inorganic phase washed with diethyl ether two times and extracted.The combined organic phases were washed with a saturated sodium chloride solution and dried with Na2S04.The organic phase was concentrated to dryness under vacuum resulting in a brown oily product.The oil was purified using silica chromatography (pentane) and then crystallized from pentane at -25 °C to afford pale yellow crystals suitable for X-ray crystal structure analysis (yield 1.16 g (39 %), m.p. 142.5 °C).

The 1-alkynyl(chloro)dimethylsilane tBuCCSiMe2Cl (1) reacts with tetraethyl-diborane(6) or 9-borabicyclo[3.3.1]nonane dimer, (9-BBN)2, to give the (Z)-1-chloro-dimethylsilyl-1-diethylboryl-alkenes 2 and 3. These alkenes react with 2-lithio-1-methylimidazole or 1-lithio-indazole by formation of LiCl and of 4, 5 and 9 together with small amounts of 6, 7 or 8 as minor products. In 4 and 5, a zwitterionic structure is present which can be alternatively described as a borane adduct of a carbene. All new compounds were characterised by 1H-, 11B-, 13C-, 15N- and 29Si-NMR spectroscopy, and the molecular structure of 5 was determined by X-ray structural analysis.

Magnetic Resonance in ChemistryVolume 36, Issue 1 p. 39-45 Research Article N-Triorganostannyl-substituted pyrroles and indoles and N-trimethylstannylcarbazole: determination of signs of coupling constants and isotope-induced chemical shifts 1Δ14/15N(119Sn) Bernd Wrackmeyer, Corresponding Author Bernd Wrackmeyer Laboratorium für Anorganische Chemie, Universität Bayreuth, D-95440 Bayreuth, GermanyLaboratorium für Anorganische Chemie, Universität Bayreuth, D-95440 Bayreuth, Germany===Search for more papers by this authorGerald Kehr, Gerald Kehr Laboratorium für Anorganische Chemie, Universität Bayreuth, D-95440 Bayreuth, GermanySearch for more papers by this authorHeidi E. Maisel, Heidi E. Maisel Laboratorium für Anorganische Chemie, Universität Bayreuth, D-95440 Bayreuth, GermanySearch for more papers by this authorHong Zhou, Hong Zhou Laboratorium für Anorganische Chemie, Universität Bayreuth, D-95440 Bayreuth, GermanySearch for more papers by this author Bernd Wrackmeyer, Corresponding Author Bernd Wrackmeyer Laboratorium für Anorganische Chemie, Universität Bayreuth, D-95440 Bayreuth, GermanyLaboratorium für Anorganische Chemie, Universität Bayreuth, D-95440 Bayreuth, Germany===Search for more papers by this authorGerald Kehr, Gerald Kehr Laboratorium für Anorganische Chemie, Universität Bayreuth, D-95440 Bayreuth, GermanySearch for more papers by this authorHeidi E. Maisel, Heidi E. Maisel Laboratorium für Anorganische Chemie, Universität Bayreuth, D-95440 Bayreuth, GermanySearch for more papers by this authorHong Zhou, Hong Zhou Laboratorium für Anorganische Chemie, Universität Bayreuth, D-95440 Bayreuth, GermanySearch for more papers by this author First published: 04 December 1998 https://doi.org/10.1002/(SICI)1097-458X(199801)36:1<39::AID-OMR209>3.0.CO;2-WCitations: 15AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Abstract N-Triorganostannyl (R3Sn)-substituted pyrroles (1) and indoles (2) [R=Me (a), Et (b), tBu (c)], N-trimethylstannyl-carbazole (3), N-trimethylstannyl-2,5-dimethylpyrrole (1d), the corresponding silicon and lead derivatives [1d(Si) and 1d(Pb)] and N-trimethylstannyl-2-methylindole (2d) were prepared and studied by multinuclear magnetic resonance (1H, 13C, 15N, 29Si, 119Sn and 207Pb NMR). The absolute signs of numerous coupling constants nJ(119Sn,13C) and 1J(119Sn,15N) (<0) were determined by appropriate 2D heteronuclear shift correlations of the type 13C/1H and 15N/1H. Precise measurement of the coupling constants 1J(119Sn,15N) from 119Sn NMR spectra by using Hahn-echo extended (HEED) polarization transfer pulse sequences enabled one to obtain isotope-induced chemical shifts 1Δ14/15N(119Sn) at natural abundance of 15N. The 1Δ14/15N(119Sn) data become more negative with increased branching of the substituent R at the tin atom and with stronger steric interactions. The latter effect is also evident from δ119Sn values and changes in the magnitude of the coupling constants 1J(119Sn,13C) or 1J(119Sn,15N). © 1998 John Wiley & Sons, Ltd. Citing Literature Volume36, Issue1January 1998Pages 39-45 RelatedInformation

A solid-state NMR method for the determination of the torsional angle of a 13C-labelled HCCH moiety is demonstrated. The method exploits the evolution of 13C double-quantum coherence under the influence of magnetic fields from the neighbouring proton spins. The experiment operates under magic-angle-spinning conditions, does not require molecular orientational order, is insensitive to shielding tensor orientations, and has high sensitivity and resolution. Experimental demonstrations and numerical simulations are shown. We obtain a torsional angle resolution of ≈ ± 20° in the neighbourhood of the cis geometry and ≈ ± 10° in the neighbourhood of the trans geometry.

(1)) The reactions of ferrocenylamine, Fc-NH2 (1), with thionyl chloride and sulfur dichloride in hexane solution in the presence of triethylamine lead to the title compounds Fc-NSO (2) and Fc(NSN)Fc (3), respectively. 2 and 3 have also been obtained in reactions of the silylated ferrocenylamine, Fc-NH(SiMe(3)) (Ib), with thionyl chloride. The ferrocenyl sulfinylimide 2 has been converted to sulfurdiimides such as Fc(NSN)Fc (3) and Fc(NSN)R (R = (t)Bu (4a), SiMe(3) (4b)) by reaction with the lithium derivative of silylated amines, LiN(SiMe(3))R (R = Fc, (t)Bu, SiMe(3)). The new ferrocenyl compounds 2-4 have been characterized by their NMR spectra, and their electrochemical behaviour has been studied. The molecular structure of Fc-NSO (2) has been determined by an X-ray structure analysis; the sulfinylimide has the Z configuration, and the -NSO group is coplanar with the cyclopentadienyl ring to which it is attached.

The reaction of cyclopentadienylpropylidenefluorene, C5H5CMe2C13H9, with stoichiometric amounts of butyllithium gives the anion [C5H4CMe2C13H9]− (1). The thermal reaction of 1 with the complexes M(CO)5(thf) (M = Cr, Mo, W) and the subsequent alkylation with CH3I leads to the alkyl complexes (η5-C5H4Me2C13H9)M(CO)3Me (3). The protonation of the anions [(η5-C5H4CMe2C13H9)M(CO)3]− (2) with acetic acid affords the hydrido complexes (η5-C5H4CMe2C13H9)M(CO)3H (4). The photolysis of complexes 3 results in the elimination of methane and formation of the complexes (η5:η1-C5H4CMe2 C13H8)M(CO)3 (5). The thermal reaction of the hydrido complexes 4b,c (M = Mo, W) and PMe3 gives cis- and trans-(η5-C5H4CMe2C13H9)M(CO)2(PMe3)H (6b,c), and the photo-induced reaction between 4b and PMe3 yields the disubstitution product trans-(η5-C5H4CMe2C13H9)Mo(CO)(PMe3)2H (7b).