Platinum and palladium complexes of [R2PCH2P(Y)R′2] and [R2PCHP(Y)R′2]− ligands, Y = O,S, or Se: 13C, 31P, 77Se, and 195Pt nuclear magnetic resonance studies and the crystal and molecular structures of trans-[PtCl(PEt3){But2PCH2P(O)Me2}][ClO4] and trans-PtCl(PEt3){Ph2PCH2P(S)But2}|[ClO4]

1988 ◽  
Vol 66 (5) ◽  
pp. 1272-1282 ◽  
Author(s):  
David Eric Berry ◽  
Jane Browning ◽  
Keith Roger Dixon ◽  
Robert Wayne Hilts

Reactions of the bisphosphine monochalcogenides, [Ph2PCH2P(Y)R2], Y = O, S, or Se, R = Ph, Pri, or But, with the chloro-bridged dimers [M2Cl4(PR′3)2], M = Pd or Pt, R′ = Et or Bun, in the presence of either NaClO4 or NaBF4 yield perchlorate and fluoroborate salts of the complex cations cis- and trans-[PtCl(PR′3){Ph2PCH2P(Y)R2}]+. In many cases both cis and trans isomers (defined by the relative orientation of the two M—P bonds) are obtained and the precise isomer distribution is a sensitive function of the substituents. Corresponding neutral complexes, cis- and trans-[PtCl(PR′3){Ph2PCHP(Y)R2}], can be synthesized either by deprotonation of the cations using NaH or by use of the salts Li[Ph2PCHP(Y)R2] in the initial bridge cleavage reactions. These and related complexes are characterized by complete 13C, 31P, 77Se, and 195Pt NMR studies and by two crystal structure determinations. The complexes I, trans-[PtCl(PEt3){But2PCH2P(O)Me2}][ClO4], and II, trans-[PtCl(PEt3){Ph2PCH2P(S)But2}][ClO4], crystallize in the monoclinic space group P21/c, respective cell dimensions: a = 15.579(2), b = 13.590(3), c = 13.578(1) Å;β= 105.96(1)°; and a = 14.002(4), b = 16.366(5), c = 15.524(5) Å; β = 106.01 (3)°. Complete X-ray diffraction studies show that both complexes contain closely square planar platinum centres with the R2PCH2P(Y)R′2 ligands coordinated via phosphorus and the Y atom so as to form five-membered chelate rings. The molecular dimensions suggest that the bond to sulphur is stronger than that to oxygen and exerts a larger trans influence.

1992 ◽  
Vol 70 (3) ◽  
pp. 751-762 ◽  
Author(s):  
Yun Xie ◽  
Chung-Li Lee ◽  
Yeping Yang ◽  
Steven J. Rettig ◽  
Brian R. James

Dibromo- and diiodo[(2-pyridyl)phosphine]palladium(II) complexes are prepared by metathesis of cis-PdCl2(PPh3−npyn)2 species (n = 1–3) using the appropriate sodium halide; py = 2-pyridyl. NMR spectroscopy, particularly,13C{1H}, is used to distinguish cis and trans isomers. The dinuclear complexes Pd2X2(μ-PPh3−npyn)2, X = halide, are synthesized via a conproportionation reaction using PdX2(PPh3−npyn)2 and Pd2(dba)3; dba = dibenzylideneacetone. Both Pd2l2(μ-PPh2py)2 and a dimethylacetylenedicarboxylate A-frame complex Pd2Cl2(μ-Ppy3)2(μ-MeO2C•C=C•CO2Me) are characterized crystallographically as head-to-tail isomers. The former crystallizes in the monoclinic space group C2/c with a = 30.992(3), b = 18.764(1), c = 13.100(1) Å, β = 100.676(5)°, and Z = 8; the data were refined to R = 0.035 for 5874 reflections with I ≥ 3σ(I). The A-frame compound is triclinic of space group [Formula: see text] with a = 13.545(2), b = 15.064(2), c = 11.991(2) Å, α = 111.56(1), β = 95.36(1), γ = 97.63(1)°, and Z = 2; R = 0.033 from 7128 reflections with I ≥ 3σ(I). The Pd2X2(μ-PPhpy2)2 complexes exist as a mixture of diastereomers because of chirality induced at the phosphorus atoms. The Pd2X2(μ-Ppy3)2 complexes in water generate the [Pd2(H2O)2(μ-Ppy3)2]2+ dication, which is isolated as various salts. The mononuclear complexes in water generate aquo and hydroxo species. Keywords: dimethylacetylenedicarboxylate adducts, palladium complexes (dinuclear), pyridylphosphines.


2009 ◽  
Vol 87 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Dana J Eisler ◽  
Stuart D Robertson ◽  
Tristram Chivers

The reaction of (THT)AuCl with (TMEDA)Na[N(TePR2)2] (R = Ph, i-Pr, t-Bu) produces a series of gold (III) complexes of the type [{R2PNP(Te)R2}Au(µ-Te)]2 (4a, R = i-Pr; 4b, R = Ph; 4c, R = t-Bu) rather than the expected homoleptic Au(I) complexes of the ditelluridoimidodiphosphinate ligands. A combination of solution- and solid-state NMR studies shows that both cis and trans isomers of 4a–4c are formed in these reactions. X-ray structural determinations of the trans isomers of 4a–4c reveal a centrosymmetric arrangement with a central four-membered Au2Te2 ring formed by the formal insertion of gold into a P–Te bond; this insertion process was shown to be reversible upon addition of PPh3 to 4a to give the monomeric gold(I) complex Ph3PAu[N{TeP(i-Pr)2}2]. The X-ray structure of cis-4b is also described.Key words: gold, tellurium, redox, X-ray structures, imidodiphosphinate.


1989 ◽  
Vol 42 (5) ◽  
pp. 741 ◽  
Author(s):  
MI Bruce ◽  
ERT Tiekink

The crystal and molecular structures of the title compound, C12F10N2.C18H22H2,are reported. The crystal structure is comprised of stacks of alternate decafluoroazobenzene and azomesitylene molecules with the vertical separation between successive molecules being approximately 3.42 � . The stacks are aligned so that the azobenzene molecules of one stack are adjacent to the azomesitylene molecules of the neighbouring stacks; there are no significant intercolumn contacts. Crystals are monoclinic, space group P21/n with unit cell dimensions a 7.197(2), b 15.432(3), c 12.513(3) � , β 96.33(2)� , and Z 2. The structure was refined by a full-matrix least-squares procedure to final R 0.059 for 915 reflections for which 1 ≥ 3.O σ(I).


1983 ◽  
Vol 61 (3) ◽  
pp. 421-426 ◽  
Author(s):  
Duncan H. Hunter ◽  
Nicholas C. Payne ◽  
Asadur Rahman ◽  
John F. Richardson ◽  
Yolanda Zea Ponce

The E- and Z-isomers of an iodo-Tamoxifen 1 (1-(p-(β-dimethylaminoethoxy)phenyl)-2-(p-iodophenyl)-1-phenyl-1-butenes) have been prepared from the corresponding E- and Z-amino-Tamoxifens 2 (2-(p-aminophenyl)-1-(p-(β-dimethylaminoethoxy)phenyl)-1-phenyl-1-butenes) and the molecular structures have been determined from three dimensional X-ray data. Crystals of E-1 are triclinic, space group [Formula: see text], with Z = 2 in a cell of dimensions a = 10.714(2), b = 14.125(3), c = 8.240(2) Å, α = 95.78(1), β = 92.91(1), and γ = 71.41(1)°; those of Z-1 are monoclinic, space group P21/n, with Z = 4 and cell dimensions a = 12.675(2), b = 19.553(3), c = 9.483(1) Å, and β = 92.22(1)°. Intensity data collected on an automated four circle diffractometer were used for full-matrix least-squares refinement on F, which converged for E-1 at R = 0.054, 2736 observations, and for Z-1 at R = 0.042, 3644 observations. The solution of these structures determines the configuration of these isomers as well as the respective amino precursors and allows an unambiguous assignment of the proton nmr spectra of 1, 2 and the Tamoxifens.


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