The Mechanism and Stereochemistry of Chlorination of Some 2,4-Dichloro-6-methylphenols; X-Ray Crystal Structures of Some Polyhalo Ketones

1994 ◽  
Vol 47 (6) ◽  
pp. 1071 ◽  
Author(s):  
JLM Gordon ◽  
MP Hartshorn ◽  
RJ Martyn ◽  
WT Robinson ◽  
GJ Wright

The additions of chlorine to the 2,4,6-trichloro-5,6-dimethyl- (7a) and 2,4,6-trichloro-6-methyl- (7b) cyclohexa-2,4-dienones to give pentachlorocyclohexenones (8)-(11) are described. The stereochemistry of some of these additions has been determined from structural studies of the chlorination products of the 2,4-dibromophenols (12). X-Ray crystal structure determinations are reported for compounds (11b), (18), (20) and (23).

1992 ◽  
Vol 45 (7) ◽  
pp. 1155 ◽  
Author(s):  
GA Bowmaker ◽  
D Camp ◽  
RD Hart ◽  
PC Healy ◽  
BW Skelton ◽  
...  

The 1 : 1 complexes of the substituted triphenylphosphine ligands mesityldiphenylphosphine and dimesitylphenylphosphine with copper(1) chloride, bromide and iodide have been the subject of single-crystal X-ray structure determinations at 295 K. All six complexes crystallize as air-stable dimeric molecules, [(PPh2Mes)CuX]2 and [ (PPhMes2)CUX]2 with each copper atom in a distorted trigonal PCuX2. coordination environment. Crystals of [(PPh2Mes)CuCl]2 (1) are monoclinic, P21/n, a 9.961(3), b 18.687(6), c 11.009(7) Ǻ, β 114.63(4)°; R was 0.049 for 2450 'observed' reflections. [(PPh2Mes)CuBrI2 (2) is monoclinic, P21/n, a 9.939(2), b 18.832(6), c 11.238(6) Ǻ, β 115.36(3)°; R was 0.046 for 1803 'observed' reflections. [(PPh2Mes)CuI]2.4/3 C6H6 (3) is rhornbohedral, R3, a 36.877(8), c 9.047(5) A; R was 0.039 for 2537 'observed' reflections. Crystals of [(PPhMes2)CuCl]2.2MeCN (4) are triclinic, Pi, a 15.783(7), b 9.570(4), c 8.914(4) Ǻ, α 72.43(3), β 76.37(3), γ 74.03(3)°; R was 0.045 for 3341 'observed' reflections. [(PPhMes2)CuBr]2.3C6H6 (5) is monoclinic, C2/c, a 9.694(6), b 30.15(2), c 20.66(2) Ǻ, β 98.00(7)°; R was 0.047 for 2117 'observed' reflections. [(PPhMes2)CuI]2.2MeCN (6) is orthorhombic, PP1nb, a 11.694(8), b 14.77(1), c 29.76(3) Ǻ; R was 0.049 for 3447 'observed' reflections. Cu-P bond lengths are: 2.196(2) A (1); 2.198(3) Ǻ (2); 2.222(5) and 2.226(5) Ǻ (3); 2.202(1) Ǻ (4); 2.197(3) A (5); 2.201(4) and 2.264(5) Ǻ (6). The geometries of the LCuX2 and CuX2Cu units are compared with data reported for other monomeric and dimeric compounds for both phosphorus- and nitrogen-based ligands L.


1985 ◽  
Vol 38 (4) ◽  
pp. 575 ◽  
Author(s):  
MP Hartshorn ◽  
WT Robinson ◽  
J Vaughan ◽  
JM White

Nitration of the bromophenols (4a) and (5a) give products of nitro-debromination . Reaction of 6-methyl-4-nitro-2-phenylphenol (5c) with nitrogen dioxide gives 2-hydroxy-2-phenylcyclohex-3-enones (8) and (9), and probably stereoisomers (10), (20), (21) and (22). The mode of ormation of these compounds is discussed. X-ray crystal structure determinations are reported for compounds (8) and (9).


1990 ◽  
Vol 43 (10) ◽  
pp. 1697 ◽  
Author(s):  
GA Bowmaker ◽  
PC Healy ◽  
LM Engelhardt ◽  
JD Kildea ◽  
BW Skelton ◽  
...  

The crystal structures of [Cu(Pme3)4]X (X = Cl , Br, I) and of [M(PPh3)4] [PF6] (M = Cu, Ag) have been determined by single-crystal X-ray diffraction methods at 295 K. The former compounds contain nearly tetrahedral [Cu(PMe3)4]+ ions on sites of m symmetry with mean Cu-P bond lengths of 2.270, 2.271 and 2.278 Ǻ for X = Cl , Br and I respectively. The latter compounds contain [M(PPh3)4]+ ions on sites of 3 symmetry. In the M =Ag complex the coordination environment is close to tetrahedral, but in the M =Cu complex the length of the axial Cu-P bond [2.465(2)Ǻ] is significantly shorter than that of the off-axis bonds [2.566(2)Ǻ]. Possible reasons for this are discussed.


2015 ◽  
Vol 71 (11) ◽  
pp. 1325-1327 ◽  
Author(s):  
Maxim Bykov ◽  
Elena Bykova ◽  
Vadim Dyadkin ◽  
Dominik Baumann ◽  
Wolfgang Schnick ◽  
...  

Hitherto, phosphorus oxonitride (PON) could not be obtained in the form of single crystals and only powder diffraction experiments were feasible for structure studies. In the present work we have synthesized two polymorphs of phosphorus oxonitride, cristobalite-type (cri-PON) and coesite-type (coe-PON), in the form of single crystals and reinvestigated their crystal structures by means of in house and synchrotron single-crystal X-ray diffraction. The crystal structures ofcri-PON andcoe-PON are built from PO2N2tetrahedral units, each with a statistical distribution of oxygen and nitrogen atoms. The crystal structure of thecoe-PON phase has the space groupC2/cwith seven atomic sites in the asymmetric unit [two P and three (N,O) sites on general positions, one (N,O) site on an inversion centre and one (N,O) site on a twofold rotation axis], while thecri-PON phase possesses tetragonalI-42dsymmetry with two independent atoms in the asymmetric unit [the P atom on a fourfold inversion axis and the (N,O) site on a twofold rotation axis]. In comparison with previous structure determinations from powder data, all atoms were refined with anisotropic displacement parameters, leading to higher precision in terms of bond lengths and angles.


1999 ◽  
Vol 54 (2) ◽  
pp. 288-290 ◽  
Author(s):  
Wolfgang Czado ◽  
Susanne Rabe ◽  
Ulrich Müller

(PPh4)2[As2Cl8] · CH3CN was obtained from PPh4Cl and S2Cl2 with As or As4S4 or AsCl3 in acetonitrile. PPh4Cl, S2Cl2 and Sb2S3 yielded (PPh4)[Sb2Cl8] CH3CN. PPh4Br and AsBr3 gave (PPh4)2[Sb2Br8]-CH3CN. AsCl2OPh (from AsCl3 and NaOPh) reacted with Ph4Br in acetonitrile in the presence of Na2Se, selenium, and HCl, affording (PPh4)2[As2Br4,2Cl3,8] · CH3CN. According to their X-ray crystal structure determinations, all products are isotypic (space group C2/c, Z=4). The centrosymmetric anions consist of two ψ octahedra sharing an edge. In the [As2Br4,2Cl3,8]2- ion the bridging positions are taken solely by bromine atoms, whereas Br and Cl atoms occupy the other halogen positions randomly.


1986 ◽  
Vol 41 (5) ◽  
pp. 560-566 ◽  
Author(s):  
Wolfgang Willing ◽  
Ulrich Müller ◽  
Udo Demant ◽  
Kurt Dehnicke

Abstract By reaction of trithiazylchloride, (NSCl)3, with PPh4[RuCl4(NO)]2 in dichloromethane the thiazylchloridenitrosyl complex PPh4[RuCl4(NO)(NSCl)] is obtained; its vacuum pyrolysis at 200-220 °C yields the thionitrosyl com plex (PPh4)2[RuCl4(NS)]2 which crystallizes from CH2Cl2 solution with four molecules of CH2Cl2. Both com pounds were charaterized by their IR spectra and by X-ray crystal structure determinations. Crystal data: PPh4[RuCl4(NO)(NSCl)], mono­clinic, space group P 21/n, Z = 4, a = 982.6, b = 1700.0, c = 1772.3 pm , β = 104.79° (2548 observed reflexions, R = 0.046); (PPh4)2[RuCl4(NS)]2·4CH2Cl2, triclinic, P1̄ , Z = 1, a = 952.9, b = 1380.0, c = 1458.5 pm , α = 112.91, β = 106.67, γ = 92.61° (3760 observed reflexions, R = 0.053). In the [RuCl4(NO)(NSCl)]⊖ ion the nitrosyl and thiazyl chloride ligands occupy ex ­ positions; bond lengths indicate double bonds in the linear Ru=N=O group, while the NSCl molecule is attached by a donor-acceptor interaction Ru-N≡S̲-Cl , although with a rather short Ru-N bond of 198 pm (N≡S 144 pm, S-Cl 213 pm). The centrosymmetric [RuCl4(NS)]22⊖ ions have chloro bridges and NS ligands in axial positions; the nearly linear Ru=N=S group has bond lengths Ru=N 175 pm and N=S 147 pm.


1982 ◽  
Vol 37 (9) ◽  
pp. 1122-1126 ◽  
Author(s):  
Ulrich Müller ◽  
Norbert Mronga ◽  
Christina Schumacher ◽  
Kurt Dehnicke

AbstractPPh4[SnCl3] and PPh4[SnBr3] were prepared by reaction of PPh4X with SnX2 in CH2X2 solutions (X - Cl, Br). The vibrational spectra of the [SnX3]⊖ ions show three SnX3 stretching frequencies, which is caused by deviations from the ideal C3v symmetry. In the crystal structure determinations these deviations show up by slightly different Sn-X bond lengths which are explained by differing hydrogen bridges to phenyl-H atoms. The isotypic crystal structures of both compounds were determined and refined from X-ray diffraction data (R values: 0.042 and 0.034). Although triclinic (space group P1̄), the structures are closely related to the tetragonal AsPh4[RuNCl4] structure type. Very pure SnBr2 is prepared by the reaction of PPh4[SnBr3] with AlBr3 in CH2Br2 solution.


1983 ◽  
Vol 36 (10) ◽  
pp. 2043 ◽  
Author(s):  
BN Figgis ◽  
JM Patrick ◽  
PA Reynolds ◽  
BW Skelton ◽  
AH White ◽  
...  

The crystal structures of the 1 : 1 adducts of FeCl3 with 2,2'-bipyridine (bpy) (1) and 1,10-phenanthroline (phen) (2), as recrystallized from nitromethane, have been determined by single-crystal X-ray diffraction methods at 295 K, being refined by least squares to residuals of 0.038 and 0.032 for 1341 and 3968 'observed' reflections; the result for (2) is a redetermination. Crystals of (1) are orthorhombic, Pbnb, a 15.013(4), b 13.510(5), c 12.471(3) Ǻ, Z 4. Crystals of (2) are triclinic, P1, a 15.823(5), b 11.021(5), c 8.200(3) Ǻ, α 80.27(3), β 76.78(3), γ 89.64(3)°, Z 2. Both complexes haw the stoichiometry (FeCl3)1(bpy,phen)1, but are formulated as cis-[Fe(bpy,phen)2Cl2] [FeCl4]; in both compounds, the Fe-N distance is c. 2.20, (trans to Cl), 2.1, Ǻ(cis to Cl), while Fe-Cl, c. 2.2, Ǻ, is short. The structure determinations of Fe2Cl6(phen,bpy)3 as [Fe(phen)2Cl2]+ [Fe(phen)Cl4]- (3) and [Fe(bpy)2Cl2]+ [Fe(bpy)Cl4]- (4) are also reported. Compound (3) (from acetonitrile solution) is triclinic, P1, a 16.502(5), b 11.857(3), c 10.653(3) Ǻ, α 84.92(2), β 72.66(2), γ 74.80(2)°, Z 2, and was refined to a residual of 0.034 for 5540 'observed' reflections. The cation geometry is similar to that of (2); in the anion, the two Fe-CI bonds trans to each other are long [2.377(1) and 2.365(1) Ǻ] while those trans to the Fe-N bonds are short [2.287(1) and 2.318(1) Ǻ]. Fe-N distances are 2.216(3) and 2.220(3) A. Compound (4) (as its nitromethane solvate) is also triclinic, P1, a 14.480(7), b 12.645(5), c 10.678(4) Ǻ, α 95.68(3), β 109.21(3), γ 9258(3)°, Z 2; a residual of 0.042 was obtained for 4962 'observed' reflections. Cation and anion metal geometries are similar to those of (3).


2019 ◽  
Vol 74 (2) ◽  
pp. 233-240 ◽  
Author(s):  
Ralf Albrecht ◽  
Phil Liebing ◽  
Uwe Morgenstern ◽  
Christoph Wagner ◽  
Kurt Merzweiler

AbstractThioether-functionalized aminosilanes R2Si(NH-C6H4-2-SR′)2 with R=Me, Ph and R′=t-Bu, Me, Ph were synthesized from the corresponding dichlorosilanes R2SiCl2 and lithiated aniline derivatives LiNH-C6H4-2-SR′. Treatment of the functionalized aminosilanes R2Si(NH-C6H4-2-SR′)2 with two eq. of n-BuLi and subsequent reaction with nickel(II) halides NiX2 (X=Cl, Br) or [Ni(acac)2(TMEDA)] led to the formation of the Ni(II) complexes [Ni{R2Si(N-C6H4-2-SR′)2}]. The X-ray single-crystal structure determinations of the nickel complexes revealed that the thioether-functionalized silylamides R2Si(NC6H4-2-SR′)22− act as tetradentate ligands. The nickel atoms exhibit a distorted square-planar coordination with Ni–N and Ni–S bond lengths in the range of 186.4(3)–186.9(2) pm and 217.5(1)–221.5(1) pm, respectively.


1991 ◽  
Vol 46 (10) ◽  
pp. 1293-1299 ◽  
Author(s):  
Jochen Dietz ◽  
Ulrich Müller ◽  
Volker Müller ◽  
Kurt Dehnicke

The title compounds have been prepared by the reactions of a potassium diselenide solution in DMF with excess selenium in the presence of tetraethyl and tetrapropyl ammonium chloride, respectively. They were characterized by X-ray crystal structure determinations.(NEt4+)2[Se52-·1 /2 Se6 · Se7]: Space group PĪ, Z = 2, 2514 observed unique reflections, R = 0.085. Lattice dimensions at —40 °C: a = 957.7(4), b = 1384.2(4), c = 1545.3(7) pm, α = 107.32(3)°, β = 97.27(4)°, γ = 105.94(3)°. The compound has an ionic structure of NEt4+ ions and chains of pentaselenide ions, which are associated with Se6 and Se7, ring molecules, forming layers parallel to (110).(NPr4)2Se11: Space group C2/c, Ζ = 4, 2198 observed unique reflections, R = 0.082. Lattice dimensions at —40 °C: a = 2364.7(5), b = 1206.8(2), c = 1609.6(3) pm, β = 118.74(3)°. The compound consists of cations (N(C3H7)4+ and spirocyclic anions Se112-, in which two Se6 rings having chair conformation are linked by a common Se atom with planar coordination. There are no short contacts between the S112- ions.


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