Coordination chemistry of a mixed donor bidentate ligand with nickel. A tetrameric enolate of sodium that binds a phosphine donor

1995 ◽  
Vol 73 (7) ◽  
pp. 1175-1180 ◽  
Author(s):  
Michael D. Fryzuk ◽  
Xiaoliang Gao ◽  
Steven J. Rettig

The preparation of a mixed donor ligand consisting of an enolate and neutral phosphine is described and its coordination chemistry with nickel reported. The phosphino ketones R2PCH2COPh (R = Cy or Pri) are prepared by the reaction of the corresponding secondary phosphines with bromoacetophenone to form the corresponding phosphonium salts [R2P(H)CH2COPh]+Br− (R = Cy or Pri); subsequent deprotonation leads to the neutral ketones. The enolates are formed by addition of NaN(SiMe3)2 to the neutral ketone. The crystal structure of the sodium enolate having isopropyl substituents at phosphorus displays a tetrameric structure in the solid state and there is an interaction of the phosphorus donor with the sodium anion: Na—P, 2.852(2) Å. The preparation of a series of nickel complexes was achieved by addition of the sodium enolate to the appropriate Ni(II) starting material. The structures of the nickel derivatives are reported. The catalytic behaviour of one of these complexes in the polymerization and oligomerization of ethylene is briefly described. Crystals of {Na[Pri2PC(H)=C(O)Ph]}4, 2b, are tetragonal, a = b = 20.790(2) Å, c = 13.539(7) Å, Z = 4, space group I41/a1; those of [Cy2PC(H)=C(O)Ph](PPh3)NiPh, 3a, are triclinic, a = 10.742(2) Å, b = 19.811(3) Å, c = 10.621(2) Å, α = 101.88(1)°, β = 119.24(1)°, γ = 91.08(1)°, Z = 2, space group [Formula: see text] and those of [Pri2PC(H)=C(O)Ph](PPh3)NiPh, 3b, are triclinic, a = 10.219(1) Å, b = 17.432(3) Å, c = 9.788(1) Å, α = 101.18(1)°, β = 100.19(1)°, γ = 85.32(1)°, Z = 2, space group [Formula: see text] The structures were solved by direct (2b) and Patterson (3a and 3b) methods and were refined by full-matrix least-squares procedures to R = 0.045, 0.044, and 0.032 (Rw = 0.038, 0.041, and 0.030) for 965, 4483, and 5085 reflections with I > 3σ(I) respectively. Keywords: nickel, sodium enolate, homogeneous catalyst, oligomerization.

1992 ◽  
Vol 70 (11) ◽  
pp. 2771-2776 ◽  
Author(s):  
Santokh S. Tandon ◽  
Laurence K. Thompson ◽  
John N. Bridson ◽  
John C. Dewan

The ligand BTIM (1,2,4,5-tetrakis(4,5-dihydro-imidazol-2-yl)benzene) reacts with cobalt(II) salts to form two series of complexes. The 1:1, dinuclear, metallocyclic derivatives [Co2(BTIM)2X2]X2 (X = Cl (I), Br (II)) involve two bis-dentate ligands in a metallocyclic structure with a large unoccupied cavity. The 2:1, binuclear derivatives [Co2(BTIM)X4] (X = Cl (III), Br (IV)) involve two metals bound to a single, bis-bidentate ligand. The crystal and molecular structures of II and III are reported. Compound II crystallized in the monoclinic system, space group P21/c, with a = 13.642(6) Å, b = 11.560(3) Å, c = 18.406(7) Å, β = 101.73(3)° and four formula units per unit cell. Refinement by full-matrix least squares gave final residuals of R = 0.060 and Rw = 0.062. Compound III crystallized in the triclinic system, space group [Formula: see text], with a = 8.367(2) Å, b = 14.254(3) Å, c = 7.649(2) Å, α = 100.99(2)°, β = 101.44(2)°, γ = 106.85(1)° and one formula per unit cell. Refinement by full-matrix least squares gave final residuals of R = 0.052 and Rw = 0.045. In the metallocyclic structure (II) the square-pyramidal cobalt(II) centres are separated by 7.599(4) Å, while in the 2:1 derivative the two tetrahedral cobalt(II) centres have a much larger separation (8.736(3) Å).


1990 ◽  
Vol 68 (8) ◽  
pp. 1277-1282 ◽  
Author(s):  
Ivor Wharf ◽  
Michel G. Simard ◽  
Henry Lamparski

Tetrakis(p-methylsulphonylphenyl)tin(IV) and tetrakis(p-methylsulphinylphenyl)tin(IV) n-hydrate have been prepared and their spectra (ir 1350–400 cm−1; nmr, 1H, 13C, 119Sn) and X-ray crystal structures are reported. The first compound is monoclinic, space group C2/c, Z = 4, with a = 21.589(6), b = 6.207(3), c = 22.861(11) Å, β = 93.80(3)° (22 °C); the structure was solved by the direct method and refined by full-matrix least squares calculations to R = 0.043 for 2755 observed reflections. It has 2 molecular symmetry with the methyl group and one oxygen atom completely disordered in both CH3S(O2) groups in the asymmetric unit. The second compound is tetragonal, space group P42/n, Z = 2, with a = b = 15.408(6), c = 6.379(2) Å (−100 °C); the structure was solved by the Patterson method and refined by full-matrix least squares calculations to R = 0.060 for 1209 observed reflections. It has [Formula: see text] molecular symmetry with the whole asymmetric unit disordered. Water molecules occupy positions on parallel 42 axes but molecular packing requirements prevent all sites having 100% occupancy giving n ~ 1 for the hydrate. Keywords: Tetra-aryltins, crystal structures, sulphone, sulphoxide, hydrogen-bonding.


1976 ◽  
Vol 54 (20) ◽  
pp. 3130-3141 ◽  
Author(s):  
Steven J. Rettig ◽  
James Trotter

Crystals of B,B-bis(p-tolyl)boroxazolidine, 1c, are trigonal, a = 25.1028(9), c = 12.4184(7) Å, Z = 18, space group [Formula: see text]. And crystals of B,B-diphenylboroxazolidine, 1a, are orthorhombic, a = 17.6420(4), b = 14.2527(3), c = 10.205(1) Å, Z = 8, space group Pbca. Both structures were solved by direct methods and were refined by full-matrix least-squares procedures to final R values of 0.057 and 0.040 for 2230 and 1828 reflections with I ≥ 3σ(I) respectively. Both molecules have structures similar to related compounds and feature intermolecular N—H … O hydrogen bonds (N … O = 2.982(2) for 1c and 2.896(2) Å for 1a). Bond lengths are: for 1c; O—C, 1.413(3), O—B, 1.478(3), N—C, 1.488(3), N—B, 1.657(3), C(sp3)—C(sp3), 1.501(4), B—C, 1.616(3) and 1.623(3), mean C—C(ar), 1.395, N—H, 0.93(2) and 0.94(2), mean C(sp3)—H, 1.00, and mean C(ar)—H, 1.00 Å; for 1a; O—C, 1.409(2), O—B, 1.476(2), N—C, 1.489(2), N—B, 1.655(2), C(sp3)—C(sp3), 1.507(3), B—C, 1.613(2) and 1.620(2), mean C—C(ar), 1.391, N—H, 0.93(2) and 0.92(2), mean C(sp3)—H, 1.00, and mean C(ar)—H, 0.98 Å. A statistical analysis of the phenyl C—C distances in compounds 1a, 1b, and 1c has provided an example of statistically significant substituent-induced bond length variation in the phenyl rings.


1984 ◽  
Vol 62 (7) ◽  
pp. 1363-1368 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Steven J. Rettig ◽  
James Trotter

Crystals of (salicylaldoximato-O,N)diphenylboron are triclinic, a = 10.125(2), b = 10.797(1), c = 14.760(2) Å, α = 89.05(1), β = 86.98(1), γ = 83.18(1)°, Z = 4, space group [Formula: see text]. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.040 and Rw = 0.048 for4145 reflections with I ≥ 3σ(I). The structure consists of two crystallographically independent, but essentially identical, molecules linked by strong [Formula: see text] hydrogen bonds to form continuous spirals along the a axis. The Ph2B moiety is chelated by the phenolic oxygen and oxime nitrogen atoms of the ligand resulting in the formation of a non-planar six-membered chelate ring. Important libration-corrected mean bond lengths are O—B = 1.516(1), N—B = 1.609(2), and C—B = 1.613(2) Å.


1992 ◽  
Vol 47 (9) ◽  
pp. 1266-1270 ◽  
Author(s):  
Siegfried Pohl ◽  
Ulrich Bierbach

The reaction of [Fe4S4I2(SC(NMe2)2)2] with racemic trans-1,2-bis(3-methylthioureido)-cyclohexane in tetrahydrofuran (thf) yields [Fe4S4I2(C6H10(NHCSNHMe)2)] · 4 thf (2). 2 crystallizes in the monoclinic space group C 2/c with a = 1471.7(2), b = 1329.7(2), c = 2339.3(3) pm, β = 107.70(1), V = 4362.3 × 106 pm3, Z = 4, R = 0.057. The cluster exhibits C2 symmetry in the solid state. The replacement of the monodentate neutral ligands results in a cluster in which the bifunctional thiourea derivative bridges two different iron sites of the slightly compressed [Fe4S4] core. The most striking feature are the differences of the Fe–Fe distances which are 269.8 pm between thiourea coordinated atoms and 280.7 pm between Fe atoms with iodide ligation. The Fe–S thiourea distance was found to be 229.3 pm.


1984 ◽  
Vol 37 (1) ◽  
pp. 35 ◽  
Author(s):  
E Horn ◽  
MR Snow

Bromide abstraction from the complexes Re(CO)3L2Br (where L = SbPh3 and L2 = bpy, dpe, tmen)* by AgF2H gives the corresponding fluoro compounds Re(CO)3L2F. Mass spectra and structural data show that the fluoride in these complexes is coordinated to the metal. The structures of Re(CO)3(tmen)F and [Re(CO)3(tmen)F]2H.HOBF3 are reported here. Crystals of Re(CO)3(tmen)F are monoclinic, space group P21/c, with a 8.202(2), b 13.115(9), c 12.048(4) � and β 102 24(3)�. A full-matrix least-squares refinement by using the absorption corrected data gave a conventional R value of 0.041. [Re(CO)3(tmen)F]2H.HOBF3 also crystallizes in the space group P21/c. The lattice parameters are: a 17.495(2), b 10.772(2), c 15.447(1) � and β ( 101.409(8)�. The final R value of a blocked least-squares calculation converged at 0.061. In these two complexes the simple Re-F distance is 2.040(4) �, in Re(CO)3(tmen)F. The Re-F distance is increased to 2.236(10)�, as a result of hydrogen bonding between the fluoride and HOBF3 in the latter compound.


1981 ◽  
Vol 59 (18) ◽  
pp. 2737-2745 ◽  
Author(s):  
Helen Elaine Howard-Lock ◽  
Colin James Lyne Lock ◽  
Graham Turner ◽  
Maruta Zvagulis

Crystals of cis-dichlorobis(cyclopropylamine)platinum(II), PtCl2(C3H5NH2)2, are monoclinic, a = 12.770(5), b = 5.838(2), c = 15.113(6) Å, β = 104.46(3)°, Z = 4, space group P21/c. The structure was solved by Patterson and Fourier syntheses and was refined by full-matrix least-squares to R = 0.057, Rw = 0.055 for 1577 reflections with I > 3σ(I). Bond lengths and angles are normal. A vibrational analysis of the compound and its d2-deuterated analogue was performed.


1995 ◽  
Vol 48 (12) ◽  
pp. 1933 ◽  
Author(s):  
CT Abrahams ◽  
GB Deacon ◽  
CM Forsyth ◽  
WC Patalinghug ◽  
BW Skelton ◽  
...  

With the facile displacement being utilized of thf from Yb(pin)2(thf)4 (pin = 2-phenylindol-1-yl, thf = tetrahydrofuran) in toluene solution, the complexes Yb(pin)2(dme)2 (dme = 1,2- dimethoxyethane), Yb(pin)2 (tmen)(tmen = N,N,N′,N′-tetramethylethane-1,2-diamine) and Yb(pin)2(diglyme)(thf) (diglyme = bis(2-methoxyethyl) ether) have been prepared from the respective ligands and Yb(pin)2(thf)4. Yb(pin)2 (diglyme) (thf) [monoclinic, space group P 21 /c, a 15.35(1), b 16.179(5), c 14.45(2) Ǻ, β 107.51(8)°, Z 4, R 0.044 for 2956 (I > 3σ(I)) 'observed' reflections] has a monomeric six-coordinate structure with transoid nitrogen donor atoms, N-Yb-N 143.6(4)° and an irregular coordination polyhedron described as either a distorted trigonal prism or a monocapped square pyramid. Attempted crystallization of Yb(pin)2 (thf) by partial desolvation of Yb(pin)2(thf)4 in hot toluene, containing a trace of dme, gave a mixture of red Yb(pin)2(thf) and orange [Yb(pin)2(dme)]2. The latter was independently synthesized by partial desolvation of Yb(pin)2(dme)2 in toluene. An X-ray crystal structure showed [Yb(pin)2(dme)]2 [monoclinic, space group P 21/c, a 11 .614(2), b 15.945(7), c 15.327(4) Ǻ, β 110.19(2)°, Z 2 dimers, R 0.070 for 2314 (I ≥ 3σ(I)) 'observed' reflections] to be a dimer with two bridging pin ligands, coordinated through nitrogen only. There is an approximately square pyramidal five-coordinate ytterbium environment with an apical dme oxygen, and with two bridging nitrogens, a terminal nitrogen, and a dme oxygen in the basal plane.


1976 ◽  
Vol 31 (9) ◽  
pp. 1166-1169 ◽  
Author(s):  
G. Huttner ◽  
H.-D. Müller ◽  
Vera Bejenke ◽  
O. Orama

The title compound 1 contains complex stabilized 1,2-diphenyldiphosphane. It crystallizes in space group P21/c with a = 1095(1), b = 1145(1), c = 1186(1) pm, β= 124.73(5)°, Z = 2. The structure has been solved by coventional methods; full matrix refinement converged at R1= 0.045.1 shows crystallographic inversion symmetry and thus contains a meso-1,2-diphenyldiphosphane ligand. The P–P-distance is 225.8 pm, the Mn–P bonds are rather short (221.6 pm).


1997 ◽  
Vol 52 (7) ◽  
pp. 810-814 ◽  
Author(s):  
Hans-Christian Böttcher ◽  
Kurt Merzweiler ◽  
Clemens Bruhn

Abstract The reaction of the phosphido-bridged metal carbonyl [FeRh(CO)6(μ-PBut2)] (1) with dppm [dppm = bis(diphenylphosphino)methane] leads to the heterobimetallic complex [FeRh(μ-CO)(CO)3(μ-PBut2)(μ-dppm)] (2) in good yields. The molecular structure of 2 was determined at room temperature [triclinic, space group P1̄, a = 9.509(6), b = 13.637(5), c = 14.926(8) Å, α = 81.38(4), β = 82.75(4), γ = 71.25(4)°]. The compound acts as a homogeneous catalyst precursor in the hydroformylation reaction of ethylene, but it decomposes during this process.


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