Unsymmetrisch substituierte Phosphinoschwefeldiimide – NMR-Untersuchungen über die Konfiguration in Lösung/ Unsymmetrically Substituted Phosphino Sulfur Diimides – NMR Studies on the Configuration in Solution

1988 ◽  
Vol 43 (8) ◽  
pp. 985-992 ◽  
Author(s):  
Max Herberhold ◽  
Stefan M. Frank ◽  
Bernd Wrackmeyer
Keyword(s):  
Nmr Spectroscopy ◽  
Low Temperatures ◽  
Room Temperature ◽  
Coupling Constants ◽  
Nmr Studies ◽  
Tert Butyl ◽  
Nmr Data

AbstractThe phosphino-substituted sulfur diimides S(N-PtBu2)2 (1), tBu;P(NSN)PRR′ (R = R′ - phenyl (2a), cyclohexyl (2b), isopropyl (2c), ethyl (2d); R = phenyl, R′ = tert-butyl (2e)) and tBu2P(NSN)tBu (3) were studied in solution by 1H, 13C and 31P NMR spectroscopy**. The coupling constants 4J(31P31P) of the compounds containing different phosphino groups, 2a-e, depend both on the nature of the solvent and the temperature. The NMR results are interpreted in accord with a rapid Z/E⇄ E/Z interconversion at room temperature and the predominance of a single configurational isomer at low temperatures. There is no indication for the presence of the “symmetrical” configurations, Z/Z or E/E respectively, in solution in appreciable amounts. 15N NMR data are also reported for a series of sulfur diimides.

Hexaethyl-2,4-dicarba-nido-hexaborane(8), Deprotonation and Complexation Studied by NMR Spectroscopy and Density Functional Theory (DFT) Calculations

2004 ◽  
Vol 59 (6) ◽  
pp. 685-691 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Hans-Jörg Schanz
Keyword(s):  
Density Functional Theory ◽  
Nmr Spectroscopy ◽  
Density Functional ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Analogous Reaction ◽  
Sandwich Complex ◽  
Dft Methods ◽  
Functional Theory ◽  
Nmr Data

Deprotonation of hexaethyl-2,4-dicarba-nido-borane(8) 2 leads first to the hexaethyl-2,4-dicarbanido- borate(1−) 3, and further deprotonation, using BuLi/KOtBu, gives the hexaethyl-2,4-dicarbanido- hexaborate(2−) 4. The reaction of 3 with FeCl2 affords the commo-ferracarborane [Fe(Et6-2,4- C2B4H)2] 5, and the analogous reaction of 4 leads to the anionic sandwich complex [Fe(Et6-2,4- C2B4)2]2− 6 which can be protonated to give 5. The complex 5 contains two hydrido ligands, each bridging the iron and two boron atoms. Reactions were monitored and the products were characterised by 11B NMR spectroscopy in solution. The geometries of the carboranes, the borates (all unsubstituted and permethyl-substituted) and the iron complexes (all unsubstituted) were optimised by DFT methods [B3LYP/6-311+G(d,p) or B3LYP/6-31+G(d)], and the relevant NMR data [chemical shifts δ11B, δ13C, δ57Fe, and coupling constants 1J(13C,1H), 1J(11B,1H), 1J(57Fe,1H), 1J(57Fe,11B)] were calculated at the same level of theory.

Tri(Terf-Butyl)plumbyl-phosphanes, Synthesis and Multinuclear Magnetic Resonance

2000 ◽  
Vol 55 (10) ◽  
pp. 939-945 ◽  
Author(s):  
Max Herberhold ◽  
Christian Köhler ◽  
Volker Tröbs ◽  
Bernd Wrackmeyer
Keyword(s):  
Magnetic Resonance ◽  
Phosphorus Atom ◽  
Coupling Constants ◽  
Tert Butyl ◽  
Nmr Data ◽  
Butyl Group ◽  
Tert Butyl Group ◽  
Multinuclear Magnetic Resonance

AbstractThe reaction of tri(tert-butyl)plumbyl-lithium (1) with various phosphorus chlorides was studied. With diphenyl- and amino(phenyl)phosphorus chlorides the formation of hexa(tertbutyl) diplumbane (2) and tetraphenyldiphosphane (3) or the respective 1,2-bis(am ino)-1,2-diphenyl- diphosphanes [e. g. 5: amino = PhCH2(tBu)N] was dominant. The presence of at least one tert-butyl group at the phosphorus atom gave access to tri(tert-butyl)plumbyl-di(tert-butyl) phosphane (4) and to tri(tert-butyl)plumbyl-amino(tert-butyl)phosphanes [amino = tBu(H)N (6), Me(Ph)N (7), PhCH2(Me)N (8), PhCH2(tBu)N (9)] via the reaction of 1 with the corresponding phosphorus chlorides. Side products were again 2 and the corresponding diphosphanes, unidentified compounds, and in two cases, bis(phosphanyl)-di(tert-butyl)plumbanes [phosphanyl = tBu(H)N(tBu)P (10), Me(Ph)N(tBu)P (11)]. Trimethylplumbyl-benzyl(methyl)- amino(tert-butyl)phosphane (12) was prepared for comparison. All compounds were characterized by their 1H , 13C, 15N (9 ),31P and 207Pb NMR data. The coupling constants 1J(207Pb,31P) are large and negative, whereas the coupling constants 1J(207Pb, 13C) are small and can be of either sign. The coupling constants 2J(31P-N-13C) of 6 - 12 indicate a preferred conformation of the substituents at phosphorus and nitrogen

Mercury(II) and cadmium(II) halide complexes of tertiary phosphine sulfides and selenides

1980 ◽  
Vol 58 (14) ◽  
pp. 1476-1479 ◽  
Author(s):  
Samuel O. Grim ◽  
Edward D. Walton ◽  
Larry C. Satek
Keyword(s):  
Room Temperature ◽  
Coupling Constants ◽  
Metal Halides ◽  
Tertiary Phosphine ◽  
Nmr Data ◽  
Halide Complexes ◽  
Reduced Temperature

Phosphorus-31 nmr data are reported for tri-n-butylphosphine selenide complexes of mercury(II) and cadmium halides and for some miscellaneous complexes of tertiary phosphine sulfides and selenides with the same metal halides. The ligands in the complexes are labile in solution at room temperature but the exchange can be "frozen out" in certain cases at reduced temperature. Selenium-77–phosphorus-31 coupling constants are less in the complexes than in the free ligands and 1JPSe decreases in each observable case with decreasing temperature. Two bond mercury-199–phosphorus-31 coupling is observed in some of the cooled solutions of the complexes.

Diminished electron density in the Vaska-type rhodium(I) complextrans-[Rh(NCBH3)(CO)(PPh3)2]

2016 ◽  
Vol 72 (7) ◽  
pp. 514-517
Author(s):  
M. R. Galding ◽  
A. V. Virovets ◽  
I. V. Kazakov ◽  
M. Scheer ◽  
S. N. Smirnov ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Nmr Spectroscopy ◽  
Electron Density ◽  
Coupling Constants ◽  
X Ray Diffraction ◽  
Metathesis Reaction ◽  
Carbonyl Carbon ◽  
Carbonyl Ligand ◽  
X Ray ◽  
Nmr Data

Vaska-type complexes,i.e. trans-[RhX(CO)(PPh3)2] (Xis a halogen or pseudohalogen), undergo a range of reactions and exhibit considerable catalytic activity. The electron density on the RhIatom in these complexes plays an important role in their reactivity. Many cyanotrihydridoborate (BH3CN−) complexes of Group 6–8 transition metals have been synthesized and structurally characterized, an exception being the rhodium(I) complex. Carbonyl(cyanotrihydridoborato-κN)bis(triphenylphosphine-κP)rhodium(I), [Rh(NCBH3)(CO)(C18H15P)2], was prepared by the metathesis reaction of sodium cyanotrihydridoborate withtrans-[RhCl(CO)(PPh3)2], and was characterized by single-crystal X-ray diffraction analysis and IR,1H,13C and11B NMR spectroscopy. The X-ray diffraction data indicate that the cyanotrihydridoborate ligand coordinates to the RhIatom through the N atom in atransposition with respect to the carbonyl ligand; this was also confirmed by the IR and NMR data. The carbonyl stretching frequency ν(CO) and the carbonyl carbon1JC–Rhand1JC–Pcoupling constants of the Cipsoatoms of the triphenylphosphine groups reflect the diminished electron density on the central RhIatom compared to the parenttrans-[RhCl(CO)(PPh3)2] complex.

Synthesis and Characterization of Indolylfulgide Photochromic Colorants

2013 ◽  
Vol 821-822 ◽  
pp. 522-526
Author(s):  
Ning Ning Lv ◽  
An Guo Sang ◽  
Yan Zhang
Keyword(s):  
Nmr Spectroscopy ◽  
1H Nmr Spectroscopy ◽  
Room Temperature ◽  
Uv Light ◽  
Synthesis And Characterization ◽  
Indole Derivatives ◽  
Thermal Stabilities ◽  
Nmr Data ◽  
New Compounds

This paper describes the synthesis of two photochromic 2-indolyl-fulgides by stobbe condensation of the corresponding 2-acyl-1,3-dimethyl-indole derivatives with diethyl isopropylidene succinate in the presence of hexamethyldisilazane potassium. The overall yields was up to 41% for 3 steps. Both prepared compounds are sensitive to UV light and change colors upon irradiation. And the two fulgides can be switched back and forth 100 times without obvious degradation. Thermal stabilities of the fulgides in acetonitrile at room temperature for 30 days and at 80 °C for 12 h were measured using UV-vis and 1H NMR spectroscopy. The absorption spectra of both forms did not exhibit any sign of degradation. The NMR data indicated that no new compounds were detected. The utilization of these materials for use in photochromic textiles were discussed.

scholarly journals Photoisomerisierung von trans-1-(3.5-Di-tert-butyl-4-hydroxyplienyl)-2-phenyldiazen / Photoisomerization of trans-1-(3,5-Di-tert-butyl-4-hydroxyphenyl)-2-phenyldiazene

1980 ◽  
Vol 35 (2) ◽  
pp. 233-236 ◽  
Author(s):  
Edgar Hofer
Keyword(s):  
Nmr Spectroscopy ◽  
Title Compound ◽  
Tautomeric Equilibrium ◽  
Tert Butyl ◽  
H Nmr ◽  
Nmr Data ◽  
Trans Isomerization ◽  
Different Temperatures ◽  
Influence Of Solvent

AbstractLight induced isomerizations of the title compound have been studied. The thermal cis-trans isomerization 3→1 occurs via the tautomeric quinonephenylhydrazone (2) as shown by 1H NMR, spectroscopy. The influence of solvent on the thermal cis-trans isomerization is discussed. 1H NMR data of 1, 2 and 3 are given. Values of the tautomeric equilibrium 1⇋2 are determined for various solvents and different temperatures.

69/71Ga and 115In NMR Spectroscopy of Lithium Tetra(tert-butyl)gallate and -indate: Spin-Spin Coupling Constants 1J(69/71Ga,13C) and 1J(115In,13C)

2009 ◽  
Vol 64 (1) ◽  
pp. 41-46
Author(s):  
Bernd Wrackmeyer ◽  
Elena V. Klimkina
Keyword(s):  
Nmr Spectroscopy ◽  
Dft Calculations ◽  
Nmr Spectra ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Tert Butyl ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling ◽  
First Time

The 13C, 69/71Ga and 115In NMR spectra of lithium tetra(tert-butyl)gallate and -indate were measured under various conditions. It proved possible to determine for the first time the coupling constants 1J(69/71Ga,13C) = 182 Hz/232 Hz and 1J(115In,13C) = 310±10 Hz for these metallates under conditions for solvent-separated ions. DFT calculations [B3LYP/6-311+G(d,p)] were carried out for organogallium compounds such as tri(tert-butyl)gallium, trimethylgallium and tetramethylgallate in order to predict and confirm coupling constants 1J(Ga,13C).

Tetra(alkynyl)silanes, a 3,6-Disila-triyne, a 3,6,9-Trisila-tetrayne, a 1,3,4,6-Tetrasiladiyne, and Bis(trimethylstannyl)ethyne. Molecular Structures and Solid-state NMR Studies

2010 ◽  
Vol 65 (2) ◽  
pp. 119-127 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Ezzat Khan ◽  
Amin Badshah ◽  
Elias Molla ◽  
Peter Thoma ◽  
...  
Keyword(s):  
Solid State ◽  
Nmr Spectroscopy ◽  
Solid State Nmr ◽  
Mas Nmr ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
Nmr Studies ◽  
X Ray ◽  
Solution State ◽  
Nmr Data

The molecular structures of three alkynylsilanes, tetrakis(ethynyl-p-tolyl)silane, 3,3,6,6,-tetramethyl- 3,6-disila-triyne, 3,3,6,6,9,9,-hexamethyl-3,6,9-trisila-tetrayne, and of bis(trimethylstannyl)- ethyne have been determined by X-ray diffraction. The same alkynylsilanes, and in addition 1,2- bis(trimethylsilylethynyl)-1,1,2,2-tetramethyldisliane, were studied by solid-state 13C and 29Si MAS NMR spectroscopy. The results of these measurements were compared with crystallographic evidence and also with relevant solution-state NMR data.

Some Applications of Ultrahigh Resolution 15N NMR Spectroscopy

1998 ◽  
Vol 53 (4) ◽  
pp. 411-415 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Ēriks Kupče
Keyword(s):  
Nmr Spectroscopy ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Absolute Magnitude ◽  
Natural Abundance ◽  
Coupling Constants ◽  
15N Nmr ◽  
Ultrahigh Resolution ◽  
Tert Butyl ◽  
15N Nmr Spectroscopy

Abstract Ultrahigh resolution 15N NMR spectra were measured for two nitroalkanes (MeNO2 la, tBuNO2 1c), two isocyanates (tBuNCO 2c, Me3SiNCO 2d), four isothiocyanates (MeNCS 3a, EtNCS 3b, tBuNCS 3c, Me3SiNCS 3d), one carbodiimide (Me3SiNCNSiMe3 4d), one keteneimine [Me3SiNCC(SiMe3)2 5d], two sulphinyl imides (tBuNSO 6c, Me3SiNSO 6d), and N-tert-butyl-pyrrole 7c, in order to determine coupling constants J(15N ,I3C) and isotope induced chemical shifts 1∆12/13C (15N) at the natural abundance of the isotopes. The values 1∆12/13C (15N) can be separated into two groups, one dealing with NC single and another one with NC double bonds. In each group (with few exceptions), the values 1∆12/13C (15N) become more negative with a decrease in the absolute magnitude of l1J(l5N ,13C)l. The corresponding values 1∆14/15N (13C) show a sim ilar behaviour. However, N-substituted pyrroles appear to be exceptional in this respect.

1,3-Distanna-2-phospha-[3]ferrocenophanes - Synthesis, Reactivity and NMR Spectroscopic Properties

1999 ◽  
Vol 54 (1) ◽  
pp. 57-62 ◽  
Author(s):  
Max Herberhold ◽  
Udo Steffl ◽  
Bernd Wrackmeyer
Keyword(s):  
Nmr Spectroscopy ◽  
Dynamic Process ◽  
Phosphorus Atom ◽  
Spectroscopic Properties ◽  
Coupling Constants ◽  
Nmr Data ◽  
Fast Movement ◽  
New Compounds

1,1,3,3-Tetramethyl-2-organo(R)-1,3-distanna-2-phospha-[3]ferrocenophanes [R = Me (2a), tBu (2b), C6H11 (2c), Ph (2d)] and one arsa-analogue 2d(As) were obtained from the reaction of 1,1′-bis(chlorodimethylstannyl)ferrocene 1 with either bis(trimethylsilyl)methylphosphane or the dilithio derivatives, Li2PR and Li2AsPh, respectively. All compounds 2 react with chalcogens (oxygen, sulfur, selenium) by cleavage of the Sn-P bonds and formation of the known 1,3-distanna-2-chalcogena-[3]ferrocenophanes. In contrast, 2d traps pentacarbonylmetal fragments [M(CO)5] to give the stable phosphane complexes [M = Cr (4d), Mo (5d), W (6d)]. The 1,1′-bis(diorganophosphanostannyl)ferrocenes [R = tBu (3b), Ph (3d)] were prepared for comparison of NMR data. The ferrocenophanes 2 are fluxional with respect to fast movement of the cyclopentadienyl rings which induces inversion at the pyramidal phosphorus atom. This dynamic process is slow in the cases of 2d(As) and of the pentacarbonyl complexes 4d - 6d. All new compounds were characterised by 1H, 13C, 31P and 119Sn NMR spectroscopy. Various 2D heteronuclear shift correlations (e.g. 31P/1H and 119Sn/1H ) were carried out for the compounds 2 and also for non-cyclic derivatives such as bis(trimethylstannyl)phenvlphosphane and -arsane in order to determine absolute signs of coupling constants [e.g. 1J(119Sn,31P) > 0 and 2J(119Sn,117Sn) < 0]. The NMR data suggest that the molecular frameworks of the ferrocenophanes 2 are not particularly strained.

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