Synthesis of heptamethylindenyl rhodium(III) complexes: molecular structures of [(η5-C9Me7)RhCl(µ-Cl)]2 and [(η5-C9Me7)Rh(PMe2Ph)Cl2]

1995 ◽  
Vol 73 (7) ◽  
pp. 981-988 ◽  
Author(s):  
Ashok K. Kakkar ◽  
Graham Stringer ◽  
Nicholas J. Taylor ◽  
Todd B. Marder

The synthesis of a series of permethylindenyl (Ind*) rhodium(III) complexes, [(η5-C9Me7)RhCl(μ-Cl)]2, [(η5-C9Me7)RhLCl2] (L = PMe3, PMe2Ph, PPh3), and [(η5-C9Me7)Rh(PMe3)2Cl]+Cl−, is reported. The structure of [(η5-C9Me7)RhCl(μ-Cl)]2, (4) was determined, confirming the dimeric nature of the compound. Ruby red crystals of 4 are monoclinic, space group C2/c, with four molecules per unit cell of dimensions a = 18.598(5), b = 10.520(3), c = 17.376(3) Å and β = 115.10(2)°. The indenyl rings exhibit minimal distortion from perfect η5 coordination to the Rh centres. A single crystal X-ray structure determination of [(η5-C9Me7)Rh(PMe2Ph)Cl2] (6) indicates a more distorted η5-coordination of the indenyl ligand, with the auxiliary ligand having the greatest trans influence, namely, the PMe2Ph group, being trans to the indenyl ring junction C—C bond. Yellow prismatic crystals of 6 are orthorhombic, space group P212121, with four molecules per unit cell of dimensions a = 8.819(1), b = 15.303(3), c = 17.296(3) Å. Keywords: rhodium, indenyl, permethylindenyl, heptamethylindenyl, phosphine complex. X-ray structure.

1992 ◽  
Vol 47 (3) ◽  
pp. 305-309 ◽  
Author(s):  
Anja Edelmann ◽  
Sally Brooker ◽  
Norbert Bertel ◽  
Mathias Noltemeyer ◽  
Herbert W. Roesky ◽  
...  

Abstract The Molecular Structures of [2,4,6-(CF3)3C6H2S]2 (1) [2,4,6-Me3C6H2Te]2 and [2-Me2N-4,6-(CF3)2C6H2Te]2 (3) have been determined by X-ray diffraction. Crystal data: 1: orthorhombic, space group P212121, Z = 4, a = 822.3(2), b = 1029.2(2), c = 2526.6(5) pm (2343 observed independent reflexions, R = 0.042); 2: orthorhombic, space group Iba 2, Z = 8, a = 1546.5(2), b = 1578.4(2), c = 1483.9(1) pm (2051 observed independent reflexions, R = 0.030); 3: monoclinic, space group P 21/c, Z = 4, a = 1118.7(1), b = 1536.5(2), c = 1492.6(2) pm, β = 98.97(1)° (3033 observed independent reflexions, R = 0.025).


1988 ◽  
Vol 41 (3) ◽  
pp. 283 ◽  
Author(s):  
GB Robertson ◽  
PA Tucker

The structures of two crystalline modifications of mer -(Pme2Ph)3H-cis-Cl2IrIII, (1), have been determined from single-crystal X-ray diffraction data. Modification (A) is monoclinic, space group P21/c with a 12.635(1), b 30.605(3), c 14.992(2)Ǻ, β 110.01(2)° and Z = 8. Modification (B) is orthorhombic, space group Pbca with a 27.646(3), b 11.366(1), c 17.252(2)Ǻ and Z = 8. The structures were solved by conventional heavy atom techniques and refined by full-matrix least- squares analyses to conventional R values of 0.037 [(A), 8845 independent reflections] and 0.028 [(B), 5291 independent reflections]. Important bond lengths [Ǻ] are Ir -P(trans to Cl ) 2.249(1) av. (A) and 2.234(1) (B), Ir -P(trans to PMe2Ph) 2.339(2) av. (A) and 2.344(1), 2.352(1) (B), Ir-Cl (trans to H) 2.492(2), 2.518(2) (A) and 2.503(1) (B) and Ir-Cl (trans to PMe2Ph)2.452(2) av. (A) and 2.449(1)(B). Differences in chemically equivalent metal- ligand bond lengths emphasize the importance of non-bonded contacts in determining those lengths.


1993 ◽  
Vol 71 (11) ◽  
pp. 1873-1889 ◽  
Author(s):  
Martin B. Hocking ◽  
Francies W. Van Der Voort Maarschalk

Dimethyl acetylenedicarboxylate was reacted with 1,2,5-triphenylphosphole under mild conditions, and four products isolated. Regardless of conditions used, every preparation gave low yields of dimethyl 3,6-diphenylphthalate coincident with loss of the phosphorus bridge. NMR data and X-ray crystal structures are provided for a yellow, and a red, 2:1 adduct. The yellow adduct, tetramethyl 1,6,7-triphenyl-6-phospha(V)-tricyclo[7.3.1.01,9]nona-3,5,7-triene-2,3,4,5-tetracarboxylate 6, crystallized in the triclinic space group [Formula: see text] (No. 2) with two molecules in the unit cell. Refinement (a = 11.259(1) Å, b = 12.947(3) Å, c = 13.784(3) Å, α = 112.25(2)°, β = 103.44(1)°, and γ = 101.80(1)°) converged at R = 0.0453 (Rw = 0.0453) for 537 parameters using 2880 reflections with I > 2σ(I). The red adduct, trimethyl 1,2,5-triphenylphosphoranylidene-4-methoxycyclopent-2-ene-5-one-2,3,4-tricarboxylate, an exocyclic phosphorane 8, crystallized in the monoclinic space group P21/c (No. 14) with four molecules in the unit cell. Refinement of this structure (a = 13.233(5) Å, b = 15.712(5) Å, c = 17.191(7) Å, α = 90°, β = 110.35(4)°, and γ = 90°) converged at R = 0.0916 (Rw = 0.0937) for 400 parameters using 2052 reflections with I > 2.5σ(I). Small amounts of a white or buff amorphous material, which could represent a polymeric product from the lost phosphorus bridge, were also obtained. Thermal rearrangement of the yellow adduct gave a colourless 6,5,3 tricyclic isomer 11, possibly via the isomeric cyclopropyl derivative 15 or the nine-membered phosphonin 7. The structure of 11 was confirmed by mild oxidation of the colourless rearrangement product to its P-oxide. This product, tetramethyl 2,3,6-triphenyl-2-phosphatricyclo[6.1.01,8.05,9]-2-oxonona-3,6-diene-1,7,8,9-tetracarboxylate 12, was also colourless. It crystallized in the orthorhombic space group Pbc21 (No. 29) with four pairs of molecules in the unit cell. Refinement of this structure (a = 8.918(1) Å, b = 22.605(4) Å, and c = 30.169(6) Å) converged at R = 0.0747 (Rw = 0.0757) for 321 parameters using 3255 reflections with I > 3σ(I). Unequivocal structures for these adducts and derivatives finally confirms, and establishes further understanding of, the complex reactions of the triphenylphosphole with dimethyl acetylenedicarboxylate.


1994 ◽  
Vol 49 (3) ◽  
pp. 430-433 ◽  
Author(s):  
Hans-Dieter Hausen ◽  
Jochen Tödtmann ◽  
Johann Weidlein

AbstractN-M ethyl-2-dimethylaluminium pyrrolide, (CH3)2Al -C4H3NCH3, crystallizes in the triclinic space group P1̄ with the lattice constants a = 700.5(1), b = 725.9(1), c = 886.8(1) pm, α = 67.69(1)°, β = 70.99(1)°, γ = 88.48(1)°, and Z = 2. This compound is isotypic with the gallium homologue [1], the shortest metal-ring contact between the two molecules of one unit cell decreases to 228.6 pm. N-dimethylgallium tetramethylpyrrolide has been synthesized from Li-N (CCH3)4 and (CH3)2GaCl. This “π-associate” crystallizes in the monoclinic space group P21/c with the lattice parameters a = 989.9(2), b = 1305.4(3), c = 878.3(2) pm, β - 112.73(1)° and 4 units per cell. Again two centrosymmetrically orientated molecules form a dimer by short (224.0 pm) intermolecular “Ga - πC ” contacts but the structure differs significant from the structure of the indium homologue [1].


2009 ◽  
Vol 64 (5) ◽  
pp. 565-569 ◽  
Author(s):  
Saied Ghadimi ◽  
Mehrdad Pourayoubi ◽  
Ali Asghar Ebrahimi Valmoozi

Mixed diamidophosphoric acid esters [(CH3)2N][p-H3C-C6H4-O]P(O)X, where X = NH(CH3) (1), NHCH(CH3)2 (2), NHC(CH3)3 (3) and p-H3C-C6H4-NH (4) were synthesized and characterized by 31P, 31P{1H}, 13C, 1H NMR, and IR spectroscopy and mass spectrometry, and single crystal X-ray diffraction analysis for the compounds 3 and 4. Compound 3 crystallizes in the monoclinic, space group P21/c with unit cell parameters a = 9.006(3), b = 16.286(5), c = 10.319(3) A° , β = 99.633(6)◦, V = 1492.2(8) °A3, Z = 4. The final R value is 0.0622 for 2074 reflections [I ≥ 2σ (I)]. Compound 4 crystallizes in the orthorhombic, space group Pna21 with unit cell parameters a = 7.0459(14), b = 20.934(4), c = 10.436(2) ° A, V = 1539.3(5) °A3, Z = 4. The final R value is 0.0530 for 3025 reflections [I ≥ 2σ (I)].


1984 ◽  
Vol 37 (10) ◽  
pp. 1991 ◽  
Author(s):  
SW Cowan ◽  
BF Hoskins ◽  
ERT Tiekink

The crystal and molecular structures of the title compounds, (C6H11)2PC(S)N(H)C6H5(1) and (C6H5)2PC(S)N(H)C6H5(2) have been determined by single-crystal three-dimensional X-ray diffraction techniques. Crystals of (1) are monoclinic, space group P21/c, with eight molecules in the unit cell of dimensions a 20.541(4), b 17.784(2), c 10.2564(9) � and β 94.54(1)�; (2) crystallizes in the triclinic space group P1 with two molecules in the unit cell which has the dimensions a 9.242(2), b 9.994(3), c 10.373(3) �, α 68.56(2), β 71.21(2) and γ 86.00(2)�. Both structures were refined by a least-squares procedure, applying anisotropic thermal parameters to all non-hydrogen atoms, with the use of 3119 and 2971 statistically significant reflections for (1) and (2) respectively; final R 0.055 for (1) and R 0.061 (Rw 0.062) for (2). The N, C(l), S moieties of both (1) and (2) display features consistent with the delocalization of π-electrons. There are notable differences in some of the bond angles between (I) and (2) which have been attributed to conformational effects arising from variations in steric pressures; this may account for the observed differences in reactivity between the two compounds.


1978 ◽  
Vol 31 (4) ◽  
pp. 781 ◽  
Author(s):  
R Mason ◽  
GR Scollary

The crystal and molecular structures of two rhodium(I) complexes with long-chain alkyne- or alkene-α,ω-diyldiphosphines have been determined by single-crystal X-ray diffraction techniques. RhCl(CO){But2P(CH2)4C≡C(CH2)4PBut2} crystallizes in the orthorhombic space group Pna21 with a 21.991 (2), b 11.915(1), c 11.890(1) Ǻ and Z 4. The structure was refined by least-squares methods to a conventional R factor of 0.097 for 1768 independent reflections (Mo Kα diffraction data). The rhodium ion is in a square-planar coordination geometry with trans-phosphorus atoms; the unsaturated (alkynyl) group is not bonded to the rhodium. Crystals of RhCl{But2P(CH2)2CH=CH(CH2)2- PBut2} are monoclinic, space group P21/c, a 20.783(12), b 8.580(4), c 14.799(9) Ǻ, β 100.70(2)°, Z 4. The structure analysis has converged to R 0.069 for 1417 reflections (Mo Kα diffractometry); the coordination geometry of the rhodium is again planar with the ethylenic group occupying a single bonding site. The effect of ring size on the rhodium-phosphorus bond lengths is discussed.


2019 ◽  
Vol 10 (3) ◽  
pp. 201-208
Author(s):  
Pokpa Haba ◽  
Adama Sy ◽  
Farba Bouyagui Tamboura ◽  
Mamour Sarr ◽  
Ibrahima Elhadji Thiam ◽  
...  

Reactions of the Schiff base N,N-dimethyl-N'-((5-methyl-1H-imidazol-4-yl)methylene) ethane-1,2-diamine (HL), synthesised in situ, with chloride or thiocyanate copper (II) salt; afforded two new mononuclear complexes, [Cu(HL)Cl2]·H2O (1) and [Cu(HL)(SCN)2] (2). These compounds have been studied and characterized by elemental analysis, IR and UV-Vis spectroscopies, electrochemistry, molar conductivity and room temperature magnetic measurements. Single crystal X-ray structure determination of the complexes revealed the presence of neutral moieties in the asymmetric unit. The mononuclear (1) crystallises in the monoclinic space group P21/c with the following unit cell parameters a = 7.4355(3) Å, b = 7.2952(3) Å, c = 26.2729(11) Å, β = 93.461(4)°, V = 1422.52(10) Å3, Z = 4, R1 = 0.033 and wR2 = 0.082 and the mononuclear complex (2) crystallises in the monoclinic space group C2/c with the following unit cell parameters a = 26.2578(7) Å, b = 7.4334(2) Å, c = 16.6237(5) Å, β = 99.089(3)°, V = 3203.95(16) Å3, Z = 8, R1 = 0.037 and wR2 = 0.104. In both complexes the ligand acts in tridentate fashion and the coordination environment of the copper atom can be described as distorted square pyramidal. The crystal lattice of the complex 1 is stabilized by electrostatic forces of attraction and O–H···Cl, C–H···O, N–H···Cl, and C–H···Cl, hydrogen bonding interactions while the crystal lattice of the complex 2 is stabilized by N–H···S and C–H···N.


1985 ◽  
Vol 63 (6) ◽  
pp. 1166-1169 ◽  
Author(s):  
John F. Richardson ◽  
Ted S. Sorensen

The molecular structures of exo-7-methylbicyclo[3.3.1]nonan-3-one, 3, and the endo-7-methyl isomer, 4, have been determined using X-ray-diffraction techniques. Compound 3 crystallizes in the space group [Formula: see text] with a = 15.115(1), c = 7.677(2) Å, and Z = 8 while 4 crystallizes in the space group P21 with a = 6.446(1), b = 7.831(1), c = 8.414(2) Å, β = 94.42(2)°, and Z = 2. The structures were solved by direct methods and refined to final agreement factors of R = 0.041 and R = 0.034 for 3 and 4 respectively. Compound 3 exists in a chair–chair conformation and there is no significant flattening of the chair rings. However, in 4, the non-ketone ring is forced into a boat conformation. These results are significant in interpreting what conformations may be present in the related sp2-hybridized carbocations.


2015 ◽  
Vol 70 (3) ◽  
pp. 191-196 ◽  
Author(s):  
Olaf Reckeweg ◽  
Francis J. DiSalvo

AbstractThe new compounds LiK[C(CN)3]2 and Li[C(CN)3]·½ (H3C)2CO were synthesized and their crystal structures were determined. Li[C(CN)3]·½ (H3C)2CO crystallizes in the orthorhombic space group Ima2 (no. 46) with the cell parameters a=794.97(14), b=1165.1(2) and c=1485.4(3) pm, while LiK[C(CN)3]2 adopts the monoclinic space group P21/c (no. 14) with the cell parameters a=1265.7(2), b=1068.0(2) and c=778.36(12) pm and the angle β=95.775(7)°. Single crystals of K[C(CN)3] were also acquired, and the crystal structure was refined more precisely than before corroborating earlier results.


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