NMR-Untersuchungen an 3,3-Difluor-2-ethyI-1,1,2-tris(diethoxyphosphoryI)-cyclopropan / NMR Investigation of 3,3-Difluoro-2-ethyl-1,1,2-tris(diethoxyphosphoryl)cyclopropane

1986 ◽  
Vol 41 (1) ◽  
pp. 63-69 ◽  
Author(s):  
Gernot Heckmann ◽  
Ekkehard Fluck ◽  
Jürgen Svara

The 19F, 31P and 13C NMR spectra in double and triple resonance mode and the temperature dependence of the NMR parameters of the title compound are discussed in detail. The rotational behavior of the phosphoryl groups is described; two of these groups show equal barriers to rotation of 75 kJ mol-1, the third one is rotating freely at room temperature.

1987 ◽  
Vol 42 (3) ◽  
pp. 260-266 ◽  
Author(s):  
Gernot Heckmann ◽  
Bernhard Neumüller ◽  
Ekkehard Fluck

Preparation and properties of the title compound 4, [N(CH3)2]2 PF2-(CH2)2-PF2[N(CH3)2]2 (2), and [N(CH3)2]2+PF-(CH2)2--PF5 (3), are described. The 1H, 19F, 31P, and 13C NMR spectra in double and triple resonance mode of 4 are recorded and discussed in detail. A 7J(HF) long-range coupling could be identified. 300 MHz-1H spectra show hindered rotation around the P-N bonds at room temperature


1976 ◽  
Vol 31 (6) ◽  
pp. 730-736 ◽  
Author(s):  
R. Rottler ◽  
C. G. Kreiter ◽  
G. Fink

The 13C NMR spectra of the ethylaluminium compounds [Al(C2H5)xCl3_x]2 x = 1, 1,5, 2 and 3 are presented and factors governing the temperature dependence of the line shape are discussed. The exchange reaction of terminal ethyl groups for chlorine ligands and ethyl ligands, resp., in ethylaluminium-sesquichloride was investigated by fitting the calculated line shapes to the observed spectra.The energy of activation of this exchange process was determined as to be 12,3 ‡ 1,5 kcal/mole. The synthesis of 13C2-[Al(C2H5)Cl2]2 is described.


1987 ◽  
Vol 42 (1) ◽  
pp. 115-117 ◽  
Author(s):  
Gernot Heckmann ◽  
Ekkehard Fluck ◽  
Peter Kuhm

Abstract Preparation and properties of a [1,3,4]thiazaphospholidine are described. The 31P. 13C and 1H NMR spectra in double and triple resonance mode are recorded and discussed in detail.


1981 ◽  
Vol 36 (1) ◽  
pp. 94-101 ◽  
Author(s):  
Helmut Burdorf ◽  
Christoph Eischenbroich

Abstract The thioanisole-π-complexes (methylthio-η-benzene)-(η-benzene)-chromium (2) and bis(methylthio-η-benzene)chromium (3) have been prepared via lithiation of bis(η-benzene)-chromium and consecutive reaction with dimethyldisulfide. 1H NMR and 13C NMR spectra of 2 and 3 as well as ESR-spectra of the corresponding radical cations 2.+ and 3.+ were recorded and analyzed. In contrast to C(η-arene)-Si and C(η-arene)-P bonds, C(y-arene)-S bonds are stable to solvolysis. With (norbornadiene)tetracarbonylmolybdenum, 3 readily forms [bis(methylthio-η-benzene)chromium]tetracarbonylmolybdenum (6) wherein 3 functions as a chelating ligand. 1H and 13C NMR evidence suggests, that at room temperature 6 undergoes rapid conformational interconversions.


1997 ◽  
Vol 52 (4) ◽  
pp. 373-376 ◽  
Author(s):  
J. Dolinšek ◽  
G. Lahajnar ◽  
B. Marin ◽  
J. Pirš ◽  
A. Sepe ◽  
...  

Abstract The temperature dependence of the proton NMR spectra of bitumen samples of different origin and quality has been measured between 400 K and 80 K. Whereas the linewidths of different samples are essentially identical above 340 K and below 240 K, there is a significant difference in the linewidth transition region around room temperature.The results show that it is possible to discriminate between bitumen samples of different composition and quality by simply measuring the proton NMR linewidth at room temperature.


1996 ◽  
Vol 61 (6) ◽  
pp. 888-900 ◽  
Author(s):  
Jiří Svoboda ◽  
Pavel Pihera ◽  
Petr Sedmera ◽  
Jaroslav Paleček

In chlorination, bromination, iodination, nitration, sulfonation, formylation, and trifluoroacetylation of [1]benzothieno[3,2-b]furan (1) the substituent enters the 2-position. The said halogenations go by the addition-elimination mechanism. When the substitution is continued, the second substituent enters the 6-position of heterocycle 1. The 1H and 13C NMR spectra have been completely assigned. Substituent effects on NMR parameters are discussed.


1992 ◽  
Vol 47 (12) ◽  
pp. 1725-1735 ◽  
Author(s):  
Hubert Schmidbaur ◽  
Benno Brachthäuser ◽  
Siegfried Gamper ◽  
Annette Schier ◽  
Oliver Steigelmann

Polyaurated carbon complexes of the type [(L–Au)6C]2+ with functionalized phosphine ligands have been prepared by the reaction of the phosphinegold(I) chlorides R(Ph)2PAuCl (R = p-C6H4-Cl 2a,p-C6H4-Br 2b,p-C6H4-CH3 2c,p-C6H4-OCH3 2d,p-C6H4-COOH 2e, p-C6H4–N(CH3)2 2f), R2(Ph)PAuCl (R = p-C6H4-N(CH3)2 2g) and R3PAuCl (R = p-C6H4-N(CH3)2 2h) with tetrakis(dimethoxyboryl)methane in HMPT at room temperature. Clearly depending on the different inductive and mesomeric effects, the preparation of the clusters with substituents like –CH3 3c, –OCH3 3d and –N(CH3)2 3f needs shorter reaction times and the products show better solubility in organic solvents than those with functional groups like –Cl 3a, –Br 3b and –COOH 3e. The 31P magnetic resonance parameters are correlated with electronic effects of the substituents, but the chemical shift of the interstitial carbon atom in the 13C-NMR spectra is largely independent of the coordinating ligands. For the phosphinegold(I) chlorides 2f–h X-ray structure analyses have been performed.


1982 ◽  
Vol 47 (3) ◽  
pp. 793-801 ◽  
Author(s):  
Jan Schraml ◽  
Martin Čapka ◽  
Harald Jancke

29Si, 13C, and 31P NMR spectra of a series of compounds of the structure (CH3)3-n(C2H5O)n.Si(CH2)mP(C6H5)2 (m = 1-6, n = )-3) are reported and assigned. Using monodeutero derivative of the compound with m = 3 and n = 0 an earlier assignment of 13C NMR spectrum is confirmed, but the assignment in the compounds with m = 4 is reversed. Introduction of ethoxy groups leads to violation of additivity rule for the 13C chemical shifts in the derivatives with m = 1. In all derivatives presence of one ethoxy group in the molecule has a profound effect on 31P chemical shift which is not changed by any further increase in the number of ethoxy groups in the molecule. The changes in 29Si chemical shifts follow the pattern known from other series of compounds. The observed trends in NMR parameters with changing n and m values can be explained by an interaction between phosphorus and oxygen atoms. Possible connections between the spectral parameters and catalysis employing the studied compounds are discussed.


1982 ◽  
Vol 37 (6) ◽  
pp. 788-789 ◽  
Author(s):  
Bernd Wrackmeyer

Abstract The 13C NMR parameters of the title compounds are assigned by heteronuclear triple resonance experiments 13C{1H,11B}. The magnitude of the coupling constants J(13C11B) corresponds roughly with J(13C13C). The chemical shifts δ13C reveal B-C(pp) π bonding which is, however, rather weak when compared with C+-C(pp) π bonding in phenylethynyl carbocations.


Sign in / Sign up

Export Citation Format

Share Document