A 31P nmr spectroscopic study of complexation of tin(II) and lead(II) by some phosphines, phosphine oxides, and related ligands, with the 31P nuclear magnetic resonance spectra of two tetratertiary phosphine tetraoxides and the analogous tetra-sulfides and -selenides

1981 ◽  
Vol 59 (1) ◽  
pp. 50-61 ◽  
Author(s):  
Philip A. W. Dean ◽  
Donald D. Phillips ◽  
Lijana Polensek

31P nmr has been used to show that, in MeNO2, M(SbF6)2 (M = Sn or Pb) forms 1:1 complexes with Ph2P(CH2)2PPh2, PhP[(CH2)2PPh2]2, MeC(CH2PPh2)3, [Formula: see text][Formula: see text]P[(CH2)2PPh2]3, and Ph2P[(CH2)2PPh]2(CH2)2PPh2. The phosphonium ligands are formed in situ. Spectra characteristics of slow inter- and intramolecular exchange were obtained in all cases except, perhaps, those involving the last two ligands, which may be involved in rapid intramolecular exchange. For the first five ligands, the maximum denticity is achieved and unambiguous one-bond M(II)—31P (M = 117/119Sn or 207Pb) coupling constants are reported and discussed. In the presence of M(SbF6)2 (M = Sn or Pb). PPh3 is protonated in MeNO2, while in acetone Sn(SbF6)2 forms a 1:1 complex with PPh3 which appears to be solvent-inserted, [Sn—O—CMe2PPh3]2+.Reduced temperature 31P nmr spectroscopy has allowed the detection of 1:2 and 1:3 (M:L) complexes of OPPh3, and 1:1 complexes of Ph2P(O)(CH2)2P(O)Ph2, PhP(O)[(CH2)2P(O)Ph2]2, and (O)P[(CH2)2P(O)Ph2]3, with both tin(II) and lead(II). The 1:1 complexes with polydentate ligands are isolable; nmr shows that the maximum denticity occurs except with the last ligand which behaves in a tridentate manner. Several two-bond M—O—P coupling constants have been obtained. Also, the changes which complexation produces in the P—P couplings are compared with changes produced in the analogous phosphine complexes.The synthesis and characterization of Ph2P(E)[(CH2)2P(E)Ph]2(CH2)2P(E)Ph2 (E = S or Se) and (Se)P[(CH2)2P(Se)Ph2]3 are reported. The 31P nmr spectra of these compounds are compared with those of the parent tetraphosphines and other members of the corresponding tetraoxide–tetrachalcogenide series.

1969 ◽  
Vol 52 (5) ◽  
pp. 1074-1092 ◽  
Author(s):  
L H Keith ◽  
A L Alford ◽  
A W Garrison

Abstract The high resolution nuclear magnetic resonance spectra of the DDT class of pesticides and related compounds are discussed, including a study of the resonances of the aromatic protons as they are affected by various substiluents. The CCl3 moiety on the α-carbon strongly deshields the ortho protons on the aromatic rings, and this deshielding effect is greatly enhanced by substitution of a chlorine ortho rather than para on the aromatic ring. These deshielding effects are explained by a consideration of the electronegativity of the substituents and the stereochemistry of the molecule. The chemical shifts and coupling constants are tabulated.


1970 ◽  
Vol 53 (1) ◽  
pp. 157-179 ◽  
Author(s):  
L H Keith ◽  
A L Alford

Abstract The high resolution nuclear magnetic resonance spectra of 35 carbamate pesticides and a major metabolite of one pesticide are discussed. The chemical shifts and coupling constants are tabulated and reproductions of the more complex or unusual spectra are included. A concentration and solvent dependence of both the NH-proton and the NCH3-proton resonances of an N-monosubstituted carbamate is discussed. Hindered rotation is observed in the N,N-dimethylcarbamates, the thiolcarbamates and the dithiocarbamates, but not in the N-methylcarbamates.


1987 ◽  
Vol 42 (12) ◽  
pp. 1515-1519 ◽  
Author(s):  
Carin Stader ◽  
Bernd Wrackmeyer

AbstractThe basic INEPT pulse sequence proved most useful for recording 15N NMR spectra at natural abundance of bis(amino)stannvlenes (1). -plumbylenes (2) and of imino-amino-λ2-phosphanes (3), where the nitrogen atoms carry bulky substituents like Me3Si-, t-Bu-, 2.4.4-trimethyl-2- pentyl-groups (t-Oct-groups) or are part of the 2.2.6.6-tetramethylpiperidinyl group. The sensitiv­ity of this technique is proved by the observation of 117/119Sn or 207Pb satellites owing to spin-spin coupling constants 1J(117/119Sn15N) and 1J(117/119Pb15N), respectively. NMR data of bis[bis(trimethylsilyl)methyl]tin (4) are reported in order to corroborate the arguments for the interpretation of the δ(15N) and 1J(119Sn15N) data. The 15N NMR data of the λ2-phosphanes (3) indicate a bonding situation similar to that in triazenes.


1979 ◽  
Vol 57 (23) ◽  
pp. 3168-3170 ◽  
Author(s):  
Henk Hiemstra ◽  
Hendrik A. Houwing ◽  
Okko Possel ◽  
Albert M. van Leusen

The 13C nmr spectra of oxazole and eight mono- and disubstituted derivatives have been analyzed with regard to the chemical shifts and the various carbon–proton coupling constants of the ring carbons. The data of the parent oxazole are compared with thiazole and 1-methylimidazole.


1982 ◽  
Vol 60 (23) ◽  
pp. 2921-2926 ◽  
Author(s):  
Philip A. W. Dean

The new stannous and plumbous complexes M(OP(C6H11)3)n2+ (n = 2 or 3, M = Sn or Pb) and [M(SP(C6H11)3)x(SeP-(C6H11)3)3−x]2+ (M = Sn or Pb) have been prepared in SO2 solution and characterized by their reduced temperature slow-exchange 31P and metal (119Sn or 207Pb) nmr spectra. No evidence could be found for complexes in which both OP(C6H11)3 and EP(C6H11)3 (E = S or Se) are coordinated to tin(II) or lead(II). The same pattern of chemical shifts is found in the 119Sn and 207Pb nmr spectra: δM(M(OP(C6H11)3)22+) < δM(M(OP(C6H11)3)32+ < δM(M(SP(C6H11)3)32+) < δM(M(SeP(C6H11)3)32+) and a monotonic but non-linear variation of δM with x for [M(SP(C6H11)3)x(SeP(C6H11)3)3−x]2+. From M(AsF6)2 in SO2 as reference, the range of the metal chemical shifts is 999–2079 ppm and 2407–7707 ppm in the 119Sn and 207Pb nmr spectra respectively. In the 31P nmr spectra, all of the appropriate two-bond M—P couplings are observed, but the fine structure expected from coupling to 31P could not always be observed in those metal nmr spectra which were measured at high field; it is suggested that these metal nmr spectra are "smeared out" by a combination of large temperature sensitivity of the metal chemical shifts and the small temperature variation allowed by the nmr spectrometer temperature controller and/or diffusion along any temperature gradients present along the length of the nmr sample.


1994 ◽  
Vol 49 (1) ◽  
pp. 100-110 ◽  
Author(s):  
Hans-Jürgen Plinta ◽  
Ion Neda ◽  
Reinhard Schmutzler

Abstract 1,3-Dimethyl-1,3-diaza-2-fluoro-5,6-benzo-1,3,2-phosphorinane-4-one (1) reacted with (COD)PtCl2 (COD = 1,5-cyclooctadiene) or K2PtCl4 to give the cis-dichloro-platinum(II) complex (2). The reactions of 1 with the tetracarbonyl norbornadiene derivatives of Cr, Mo and W furnished the complexes 3 - 6 . In the case of the chromium and tungsten complexes the trans-isomers 3 and 6 were formed, due to a cis-trans-isomerization. Room temperature and low temperature 31P NMR spectra of a mixture of 5 and 6 show no significant temperature dependence of the cis-trans equilibrium. The reaction of 1 with the pentacarbonyl tetrahydrofuran derivative of W led to the product 7. The spirophosphoranes 8 and 9 were obtained in low yields. The analogous reactions of 10, 15 and 20 with (COD)PtCl2 and the tetracarbonyl norbornadiene derivatives of Cr and Mo furnished the coordination compounds 11-14, 16-18, 21 and 23. In the case of all chromium complexes only the trans-isomers 11,16 and 21 were formed, whereas in the case of molybdenum cis-trans-isomer mixtures 12 and 13, as well as 17 and 18 were obtained. An attempt to obtain the cis-isomer of the molybdenum complex 22 failed. In the case of platinum the expected cis-complexes 14 and 23 were formed, while the attempted synthesis of 19 was unsuccessful. All these results are interpreted in terms of both steric and electronic factors. The ligands 1, 10, 15 and 20 coordinate via phosphorus. The validity of the concept of hard and soft acids and bases (HSAB) was confirmed. The characterization of 2 - 7 , 11-14, 16-18, 21 and 23 rests, especially, on their 1H, 13C and 31P NMR spectra, and their mass and infrared spectra. 31P - 31P coupling constants 2J(PP) for the cis-coordinated complexes 4, 5 and 14 involving two equivalent phosphorus ligands are also reported.


1972 ◽  
Vol 27 (4) ◽  
pp. 368-376 ◽  
Author(s):  
Wolfgang Haubold ◽  
Ekkehard Fluck

Preparation and properties of linear and branched phosphorus nitride chlorides with chlorosulfurylimide endgroups are described.The nmr spectra of phosphorus (V) nitride chlorides and phosphorus (V) sulfur (VI) nitride chlorides are compared and discussed. Chemical shifts δ31p and δ19F , structure of resonance signals and coupling constants are tabulated.


2011 ◽  
Vol 3 (3) ◽  
pp. 587-597 ◽  
Author(s):  
M. I. Hossain ◽  
D. Debnath ◽  
M. Younis ◽  
M. A. Bari ◽  
M. A. J. Miah

A series of thermally stable organic polymers [poly(2,5-diethynylpyridine] (5), [poly(1,4- diethynyl benzene)] (6), [poly(2,5-dialkyl-p-phenyleneethynylene)] (7), and [poly(p,p-diethynylbiphenyl)] (8), were synthesized by the reaction between diterminal aryleneethynylene, [HCCArCCH] {Ar = C5H5N (1); Ar = C6H6 (2); Ar = C6H4(CH3)2 (3); Ar = C6H4-C6H4 (4)} and CuCl in pyridine by Hay’s oxidative coupling method. Then the organometallic polymers [Ph (PnBu3)2Pt-C≡C-(Ar-C≡C-C≡C)n-Pt((PnBu3)2Ph] {Ar = C5H5N (9); Ar = C6H6 (10); Ar = C6H4(CH3)2 (11); Ar = C6H4-C6H4 (12)}   were synthesized by the reaction of organic polymers 5, 6, 7 and 8 with metal precursor (PnBu3)2 PtPhCl in diethylisopropileamine with good yield. These metal-linked polymers were characterized by IR, 1H-NMR, 13C-NMR and 31P-NMR spectra. Finally the molecular weight of the organometallic polymers (9, 10, 11 and 12) was determined by gel permeation chromatography (GPC). It is clearly observed from GPC that the polymers were synthesized with different degree of polymerization. Keywords:  Organometallic polymers; Hay’s Oxidative coupling; GPC. © 2011 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. doi: 10.3329/jsr.v3i3.7293               J. Sci. Res. 3 (3), 587-597 (2011)


1979 ◽  
Vol 57 (9) ◽  
pp. 958-960 ◽  
Author(s):  
Howard C. Clark ◽  
Charles R. Milne

The 31P nmr spectra of the compounds cis-[M(CH3)(L)diphos]PF6, where M = Pd, Pt; L = 4-C5H4NX; X = CH3, H, NMe2, COOMe, COMe, CN; diphos = 1,2-bisdiphenylphosphino ethane, have been recorded. The 31P chemical shifts and 31P–195Pt coupling constants decrease regularly as the ρ values of the substituent on pyridine decrease. These trends are attributed to decreasing lone pair donation from phosphorus as the electron donating ability of the other ligands on the metal increases. The trans influence of the coordinated pyridine molecule, as measured by J(195Pt–31P), is greater than its cis influence on the phosphorus atoms.


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