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

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.

1980 ◽  
Vol 35 (7) ◽  
pp. 832-837 ◽  
Author(s):  
Samuel O. Grim ◽  
Larry C. Satek ◽  
J. Dale Mitchell

The synthesis via the useful lithium reagent intermediate, (C6H5)2P(S)CH2Li, is reported for eight compounds of the type [(C6H5)2P(X)][R2P(X)]2CH, where R is methyl or phenyl and X is an electron pair, oxygen, or sulfur in various combinations. Two related compounds with three and four phosphorus atoms, respectively, per molecule have also been prepared from the same lithium reagent. Tris(diphenylthiophosphoryl)methane has three equivalent phosphorus atoms as indicated by the room temperature phosphorus-31 NMR spectrum, but at reduced temperature a favored conformation exists which has two equivalent phosphorus atoms and a unique one. Other phosphorus-31 and proton NMR data are reported


1988 ◽  
Vol 43 (8) ◽  
pp. 985-992 ◽  
Author(s):  
Max Herberhold ◽  
Stefan M. Frank ◽  
Bernd Wrackmeyer

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.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ramanshu P. Singh ◽  
Shakti Yadav ◽  
Giridhar Mishra ◽  
Devraj Singh

Abstract The elastic and ultrasonic properties have been evaluated at room temperature between the pressure 0.6 and 10.4 GPa for hexagonal closed packed (hcp) hafnium (Hf) metal. The Lennard-Jones potential model has been used to compute the second and third order elastic constants for Hf. The elastic constants have been utilized to calculate the mechanical constants such as Young’s modulus, bulk modulus, shear modulus, Poisson’s ratio, and Zener anisotropy factor for finding the stability and durability of hcp hafnium metal within the chosen pressure range. The second order elastic constants were also used to compute the ultrasonic velocities along unique axis at different angles for the given pressure range. Further thermophysical properties such as specific heat per unit volume and energy density have been estimated at different pressures. Additionally, ultrasonic Grüneisen parameters and acoustic coupling constants have been found out at room temperature. Finally, the ultrasonic attenuation due to phonon–phonon interaction and thermoelastic mechanisms has been investigated for the chosen hafnium metal. The obtained results have been discussed in correlation with available findings for similar types of hcp metals.


1969 ◽  
Vol 22 (1) ◽  
pp. 121 ◽  
Author(s):  
IE Grey ◽  
PW Smith

The variation of magnetic susceptibility with temperature for a number of binuclear halide complexes of molybdenum of formula A3IMo2X9 (A = Cs, Et4N, Et3NH; X = Cl, Br) has been studied over the range 90-400�K. The magnetic behaviour is consistent with that expected for magnetically isolated exchange-coupled pairs of molybdenum atoms. The coupling is interpreted as occurring mainly by direct metal-metal interaction rather than superexchange.


1984 ◽  
Vol 39 (7) ◽  
pp. 915-920 ◽  
Author(s):  
Herbert Meier ◽  
Thomas Molz ◽  
Heinz Kolshorn

The 1H and 13C NMR data of thiophene 1,1-dioxide (3) and related compounds, especially of the precursor 2 and the consecutive product 5 are evaluated by computer simulation and multiple resonance. Chemical shifts and coupling constants reveal that 3 has the character of a cyclic diene. Diatropic or paratropic effects can be excluded.


2003 ◽  
Vol 58 (1) ◽  
pp. 59-73 ◽  
Author(s):  
Günter Paulus Schiemenz ◽  
Christian Näther ◽  
Simon Pörksen

Abstract The 31P NMR data of non-quaternary (8-dimethylamino-naphth-1-yl)phosphonium salts, with emphasis on the 1J(31P, 1H) coupling constants, where scrutinized for their potential to yield information about N→P dative interactions. As for δ (29Si) and 1J(29Si, 1H) in the isosteric silanes, the data do not permit conclusions in favour of such interactions. 1J(31P, 1H) of bis(8-dimethylaminonaphth- 1-yl)phosphine in conjunction with the distances d(N···P) invalidates the basic assumption on which the claim of dative N→P/Si bonding in such phosphorus and silicon compounds rests, viz. that N···P/Si distances of ca. 270 pm are evidence for P/Si-hypercoordination. No evidence for hydrogen bonds N···H-P was found.


2004 ◽  
Vol 59 (6) ◽  
pp. 685-691 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Hans-Jörg Schanz

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.


1990 ◽  
Vol 45 (3-4) ◽  
pp. 459-463 ◽  
Author(s):  
T. J. Bastow ◽  
S. N. Stuart

Abstract The nuclear quadrupole interaction tensors of 14N and 39K in potassium nitrate at room temperature have been determined from nuclear magnetic resonance (NMR) rotation studies of single crystals at 9.4 T. Values for the coupling constants and asymmetry parameters at 296 K are:14N: e2 qQ/h = 751 kHz, η = 0.022; 39K: e2 qQ/h = 1326kHz, η = 0.171. The temperature dependence, on approaching the order-disorder phase transition near 401 K, is linear.


2005 ◽  
Vol 60 (3) ◽  
pp. 251-258 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Oleg L. Tok ◽  
Azim Khan ◽  
Amin Badshah

The reaction of the di(alkyn-1-yl)silanes Me2Si(C≡CSiMe2H)2 1a and Me(H)Si(C≡CSiMe2H)2 1b with triethylborane was studied. In the case of 1a, the 4-ethyl-3-diethylboryl-1,1-dimethyl-2,5- bis(dimethylsilyl)-1-sila-2,4-cyclop entadiene 2a was the sole product. In the case of 1b, the analogous silole 2b was formed along with two other products which were identified as di(alkenyl)silanes 3b and 4b, in which different types of electron-deficient Si-H-B bridges could be detected. All products were characterised by consistent sets of solution NMR data (1H, 11B, 13C and 29Si NMR). The coupling constants 1J(13C,13C) were measured for 2a and calculated by using DFT methods (B3LYP/6-311+G(d,p) level of theory)


1989 ◽  
Vol 44 (3) ◽  
pp. 288-292 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Klaus Horchler ◽  
Hong Zhou ◽  
Michael Veith

1,3-Diisopropyl-2,2-dimethyl-1,3,2,4λ2-diazasilastannetidine (1b) and -plumbetidine (2b) are dimeric [(1b)2, (2b)2] in solution. At room temperature the structure of (1b)2 is fluxional. The dynamic behaviour is interpreted - on the basis of 1H. 13C, 29Si and 119Sn NMR data - as an intramolecular process in which the four-membered rings keep their identity. Such a process involves either concerted opening of the two coordinative Sn - N bonds and mutual slippage of the two rings, or consecutive cleavage of one of the coordinative Sn - N bonds and rotation about the other one. At room temperature the dimer (2b)2 is in equilibrium with its monomer 2b, whereas at low temperature the dynamic process corresponds to that established for (1b)2. In solutions which contain a mixture of the dimers (1b)2 and (2b)2, the presence of the mixed dimer 1b/2b can be proved unambiguously by consistent 29Si, 119Sn and 207Pb NMR data.


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