Structure oftrans-dichlorooxobis(triphenylphosphine)rhenium(V), ReCl2O(OEt)(Ph3P)2

C₃₈H₃₅Cl₂O₂P₂Re,M _r=842, triclinic,P¯1,a=17.71(2),b=11.33(1),c=9.82(1) Å,=114.60(3),=90.84(3), =78.05(3),V=1747(2) ų,D _m(flotation)=1.60,D _x=1.60 Mg m^–3 forZ=2, MoK, =0.7107 Å,=41.6 cm^–1,F(000)=836, room temperature. The structure was solved by standard methods from diffractometer data and refined to a conventionalR of 3.4% for 5412 observed reflections. The Re atom is six coordinate octahedral withtrans-Cl atoms andtrans-Ph₃P groups. Relevant bond distances are: Re-P 2.533(1) and 2.535(1) Å, Re-O(ethoxo) 1.888(4) Å, and Re-O(oxide) 1.699(4) Å. The ethyl chain is partially disordered.     

Crystal structure of 14, α-hydroxy,sandarocopimar-7, 15-diene-19-oic acid

C₂₀H₃₀O₃, M _r =318.46, Monoclinic,P2₁,a=12.232(2) ,b=11.491(2) ,c=14.160(3) , =115.2°(3),V=1800.3(7) ³,Z=4,D _x =1.18 Mg m^–3, (CuK)=1.5418 , =5.3 cm^–1,F(000)=696,T=298 K. FinalR=0.044 for 2645 reflections withI>2. The two crystallographically independent molecules in the unit cell adopt essentially similar conformations. The structure reveals atrans relationship between the hydrogen at C(9) and the methyl group at C(20). The stereochemistry at C(13) is S. Apart from van der Waals forces the structure is stabilized by hydrogen bonds.     

A new monoclinic crystal phase of [Bu4N][Ni(dmit)2]

The crystal structure of the title compound, tetrabutylammonium bis(2-thioxo-1,3-dithiole-4,5-dithiolato)nickelate(III), [N(C₄H₉)₄][Ni(C₃S₅)₂], is the fourth known phase of this polymorphous compound. It is monoclinic space group P2₁/c, with a = 20.040(2) Å, b = 13.1151(17) Å, c = 12.1093(15) Å, = 105.456(15)°, and V = 3067.5(6) ų with Z = 4, for D _calc = 1.503 g cm^–3. The [Ni(dmit)₂] anion packing arrangement consists of arrays of side-on touching anions and these arrays are connected via head-to-tail close S S contacts.     

On the organoaluminum chemistry of multidentate phosphine ligands. Reaction of trimethylaluminum with bis(diphenylphosphino)methane: Synthesis and molecular structure of [Al(CH3)3]2[(C6H5)2PCH2P(C6H5)2]

Reaction of an excess of trimethylaluminum with bis(diphenylphosphino)-methane in heptane affords the crystalline complex [A1(CH₃)₃]₂[(C₆H₅)₂PCH₂P(C₆H₅)₂]. The title compound crystallizes in the triclinic space group P¯1 with unit cell parametersa=10.053(6),b=11.017(6),c=15.908(8) Å,=85.58(4),=71.80(4), =77.49(4)°,V=1634(1) ų, andD _c=1.07 g cm^–3 forZ=2. Least-squares refinement based on 2924 observed reflection with intensitiesI3I) in the range 2.00245.0° converged atR=0.050 (R _w=0.067). The Al-P distances are 2.585(2) and 2.521(2) Å, and the P-C-P angle is 121.4(2)°.     

Crystal and molecular structure of OC(CoC5H5)3(CF3CCCF3)

The structure of the title compound has been confirmed by an X-ray diffraction analysis, and refined by full-matrix least squares. The crystals are mono-clinic:a=9.171(3),b=25.176(15)c=9.192(3) Å,=117.08(3)°,Z=4,D _x =1.976g cm^–3,=2.66mm^¯1, space groupP2₁/n (No. 14). The finalR value is 5.7%. Interatomic distances and bond angles are compared with those reported in related molecules.The preferred name of this compound according to the IUPAC rules is ₃-[11–2-bis(trifluoromethyl)vinylene]- ₃-carbonyl-tris (-cyclopentadienyl)-triangulo-tricobalt.     

Room temperature ligand fragmentation in the reaction between PhCCo3(CO)9 and Ph2PN(Me)N(Me)PPh2. X-ray diffraction structure of PhCCo3(CO)8[Ph2PP(O)Ph2]

The cobalt cluster PhCCo₃(CO)₉ reacts with the bis(phosphanyl)hydrazine ligand bis(diphenylphosphino)dimethylhydrazine (dppdmh) in CH₂Cl₂ with added Me₃NO to give the monosubstituted cluster PhCCo₃(CO)₈[Ph₂PP(O)PPh₂] as the major isolable product. The solid-state structure of this new cluster was unequivocally established by X-ray diffraction analysis, which has confirmed the presence of a noncoordinated (O)PPh₂ moiety. PhCCo₃(CO)₈[Ph₂PP(O)Ph₂] crystallizes in the triclinic space group P , a = 12.036(2), b = 12.037(2), c = 15.124(3) Å, = 84.82(1)°, = 89.44(2)°, = 60.09(1)°, V = 1890.0(6) ų, Z = 2, and d_calc = 1.540 g/cm³.     

Structure of a platinum(II) complex containing a benzothiazole derivative: [NEt4][Pt(3,4-dsb)Br3]

Tetraethylammoniumtribromo[2-(3.4-dimethoxy)styrylbenzothiazole]platinate(II), [(C₂H₅)₄N]-[PtBr₃(C₁₇H₁₅NO₂S)], monoclinic,P2₁/c,a=13.454(7),b=11.991(3),c=19.004(5) Å, = 108.92(3)°,V=2900(4) ų,Z=4,D _r=1.975 g cm^–3, (MoK)=0.71073 Å, =95.59 cm^–1,F(000)=1656,T=303 K, finalR=0.051 for 2262 unique observed reflections. The structure was solved by heavy atom and Fourier methods. The molecule is nearly planar, with a dihedral angle of only 3.57(7)° between the benzothiazole and phenyl rings. The C–S–C angle in the thiazole ring is 91(1)°.     

Synthesis and structure of (η5-C5H5)2Hf(η1-NC4H4)2

The crystal structure of (⁵-C₅H₅)₂Hf(¹-NC₄H₄)₂ has been determined from X-ray data measured by counter methods. The title compound is isostructural with (⁵-C₅H₅)₂Zr(¹-NC₄H₄)₂, and crystallizes in the monoclinic space groupP2₁/c (C _2h ⁵ , No. 14) with unit cell constantsa=9.605(3),b=8.174(3),c=19.487(4) Å, =90.85(3)°, andZ=4 forD _c=1.91 gcm^–3. Full-matrix least-squares refinement gave a finalR value of 0.068 for 2154 independent observed reflections. The two cyclopentadienyl rings are ⁵-coordinated to the hafnium atom at an average Hf-C(⁵–) distance of 2.51(1) Å. The Hf-N-centroid (-pyrrolyl) angles average 166°.     

Molecular structure of N-(2-phenylethyl)amide of α-(1,1-ethylenedioxy)-ethyl γ-hydroxybutyric acid (I) and1H NMR spectra of (I) and N-(p-methoxybenzyl)derivative (III)

The spectroscopic and X-ray investigation of the N-(2-phenylethyl) amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid are reported. The¹H NMR spectra for the title structure and for the N-(p-methoxybenzyl) amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid are given. The N-(2-phenylethyl)amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid, C₁₆H₂₃O₄N, crustallizes in the monoclinic space groupP2 ₁/c witha=21.547(5),b=6.333(2),c=11.822(3) Å and =101.01(2)°. The dioxolane ring has a half-chair conformation with C₂(O3)=2.4° and ||_av=18.2°. The inconsiderable deviations from planarity of the six atoms of the amide group are caused mainly by twist around the C4–N1 bond and out-of-plane bending at the N1 atom ((C4–N1)=4°, X_N =7°, X_c =0.4° ). The amide group plane is nearly coplanar with the phenyl ring. The molecules are connected by two intermolecular hydrogen bonds.     

Crystal structure of an intermediate in the synthesis of artemisinin

C₁₄H₂₂O₃,M _r =238.33, P2₁2₁2₁,Z=4,a=6.892(2),b=11.453(1),c=17.159(5) Å. [1R–[1(R^*), 4, 4a, 8a]]–,4-Dimethyl-decahydro-7-oxo-1-naphtaleneacetic acid. The cyclohexane ring adopts a chair conformation and thecis-fused cyclohexanone ring is in a slightly distorted chair conformation. The molecular packing involves an hydrogen bond and C–H...O contacts.     

Crystal structure of form 1, magnetic properties and polymorphism of bis (NN-di-(n-propyl)dithiocarbamato iron (III) iodide

The crystal structure of bis (NN-di(n-propyl)dithiocarbamato iron(III) iodide, Fe^III(S₂CN₆H₁₄)₂I, has been determined by the heavy-atom method and refined toR=0.055 for 3487 reflections withI(hkl)>3I(hkl). The crystals are triclinic,C¯1,Z=8,a=27.644(6),b=19.186(4),c=8.694(2) Å,=87.79(1),=88.72(1), =101.87(2)°. The I-Fe bond lengths are different in the two moleculesA andB in the asymmetric unit, having values of 2.642 Å (2.655) and 2.612 Å (2.634) respectively (libration-corrected values given in parentheses). The measured effective magnetic moment _eff3.89 BM, independent of temperature (93-353K), suggests a spinS of 3/2 with three unpaired electrons for Fe^III.     

Crystal structure of μ-adeninatobis (methylmercury (II)) perchlorate monohydrate

The title compound belongs to the triclinic space groupP¯1,a= 8.189 Å,b = 9.863 Å,c = 10.726 Å, = 69.93 °, = 68.62 °, = 73.66 °, andZ = 2. The structure was refined on 1337 observed reflections to anR factor of 0.042. The crystals contain [adeninato(CH₃Hg)₂]⁺ complex cations in which mercury is linearly bonded to N(7) and N(9) of a deprotonated adenine ring. Centrosymmetrically related complex cations are paired via two N(6)-H(6) N(l) hydrogen bonds. Those planar units are stacked in the crystal with a distance of 3.4 Å between rings. The water molecule and the ClO₄ ^-ion are involved in hydrogen bonding and HgO contacts. This structure identifies N(7) as the best residual coordination site after H(9) has been substituted by CH₃Hg.     

Synthesis and crystal structure of a terephthalato-bridged copper(II) complex [Cu2(tpt)(bpy)2(H2O)4] [Cu2(tpt)3 (bpy)2(H2O)2]

A terephthalato-bridged copper(II) complex [Cu₂(tpt)(bpy)₂(H₂O)₄][Cu₂(tpt)₃(bpy)₂ (H₂O)₂] (1) (tpt = terephthalate, bpy =; 2,2'-bipyridine) was synthesized by the reaction of Cu(ClO₄)₂ 6H₂O and terephthalic acid in the presence of 2,2'-bipyridine in H₂O solution. Crystal structure of 1 was determined by X-ray diffraction analysis in the triclinic space group P , with a = 10.7327(10) Å, b = 11.1658(11) Å, c = 17.3768(16) Å, = 108.063(2), = 91.064(2), = 116.721(2), V = 1737.5(3) ų, and Z = 2. Both the anion and the countercation in 1 are copper(II) complexes linked by terephthalate bridges in the bis(monodentate) (syn–anti) mode. The anion and the countercation are also linked by two hydrogen bonds between coordinating water molecules and terephthalate ligand.     

Aromatic amines and their derivatives,Part 2. Synthesis,spectroscopic properties,and molecular and crystal structure ofN-acetyl-4,N-dimethyl-6-(N-acetyl-p-toluidinomethyl)aniline

The synthesis and selected aspects of the UV, IR, and¹H NMR spectra of the title compound are described. The crystals of the title compound are triclinic witha=12.999(9),b=8.911(4),c=9.199(5) Å;=105.56(3),=113.50(4), =92.53(3)°;Z=2; space groupP¯1. Its X-ray crystal structure analysis provides information regarding the conformational features of the amide linkage when no intermolecular hydrogen bonding involving this group is present. The X-ray study shows that the C-N bond is longer [1.363(4) Å] than that found normally in peptide molecules. The compound shows a peculiar disorder involving one of the two amide groups present in the molecule. The conformation of theN-methyl acetanilide moiety and its relation to the¹H NMR spectrum of the compound are discussed.     

Antimony(III) fluoride: inclusion complexes with crown ethers

Four crystalline molecular complexes between antimony(III) fluoride and 18-membered crown ethers have been obtained and their structures investigated by single crystal X-ray diffraction techniques: [18-crown-6·SbF₃], C₁₂H₂₄F₃O₆Sb,P2₁2₁2₁,a=8.328(4),b=11.573(4),c=18.094(4),V=1744(1)³,Z=4; [benzo-18-crown-6·SbF₃], C₁₆H₂₄F₃O₆Sb,P2₁/n,a=10.490(2),b=13.714(1),c=13.442(2), =101.94(1)°,V=1892(1)³,Z=4; [cis-syn-cis-dicyclohexano-18-crown-6·SbF₃·CH₃OH], C₂₁H₄₀F₃O₇Sb,P2₁/n,a=8.270(4),b=23.386(3),c=12.772(1), =96.31(2)°,V=2455(1)³,Z=4; [cis-anti-cis-dicyclohexano-18-crown-6·SbF₃], C₂₀H₃₆F₃O₆Sb,Pna2₁,a=21.091(8),b=12.829(5),c=8.437(3),V=2283(2)³,Z=4. All species are the perching-type complexes with the antimony fluoride above the cavity and the metal lone pair pointed toward the center of the crown ring. The antimony atom interacts with all six crown oxygen atoms with Sb–O distances of 2.837(2)–3.344(2) . The antimony atom is displaced from the least square plane of the crown oxygen atoms at the distances of 1.288–1.383 .     

Trimethylamine-N-oxide induced disproportionation of Re2(CO)10: Synthesis and X-ray crystal structure of [fac-Re(CO)3(ONMe3)3] [ReO4]

An attempted synthesis of [Re(CO₃) (-OH)]₄,1, by reacting Re₂(CO)₁₀ with an excess of NMe₃O in THF resulted instead in isolation of a disproportionation product, [fac-Re(CO)₃(ONMe₃)₃][ReO₄],2. The structure of2 was determined via X-ray crystallography: tri-clinic,P1^¯,a=9.499(5),b=9.841(2),c=13.448(2)Å,=109.92(2),=106.89(3), =93.15(4)°,D _calc=2.22 g^–3 andZ=2. Least-squares refinement based on 1606 observed (I>3(I)) reflections gave final values ofR=0.040 andR _w=0.047. The cation is a distorted octahedron that exhibits several structural manifestations of steric crowding among the bulky NMe₃O ligands.     

Crystal structures of two therapeutically active 2-imidazolines: naphazoline nitrate and tymazoline hydrochloride monohydrate

Naphazoline·HNO₃ (1): C₁₄H₁₅N₃O₃,M _r =273.3, crystallizes in the orthorhombic space group Pbca(Z=8) witha=12.028(1),b=14.408(2) andc=15.894(2) Å,V=2754.4 ų,D _x =1.318 g cm^–3,=0.70 mm^–1, (CuK)=1.54178 Å,F(000)=1152. FinalR=0.092 andwR=0.088 for 1348 observed reflections collected on a diffractometer. The structure was solved with direct methods, it shows two distinct positions of the naphthyl group with populations about 0.5, which differ by a 180 rotation. As in other arylmethyl-2-imidazolines, the imidazoline ring is approximately perpendicular to the aromatic ring. The molecules are linked by two hydrogen bonds N(3)-HO (nitrate anion)H-N(1) into infinite chains running along the 2₁ axis in the [100] direction. Tymazoline·HC1·H₂O (2): C₁₄H₂₃ClN₂O₂,M _r =286.8, crystallizes in the monoclinic space groupP2₁/n (Z=4) witha=8.136(1),b=10.015(1),c=18.601(1) Å and,=97.20(1)°,V=1503.7 ų D _x =1.266 g cm^–3,=2.27 mm^–1, (CuK)=1.54178 Å,F(000)=636. FinalR=0.115 andwR=0.119 for 3073 observed reflections collected on a diffractometer. The structure was solved with direct methods. Unlike other aryloxymethyl-2-imidazolines, the molecule is almost planar with an angle of 12.8(2)° between the two rings. Hydrogen bonding networks consist of N(1)-HO (water)Cl^–H-N(3) chains joined by an additional link O(water)-HCl^– between chains running in opposite directions.     

Structural characterization of oxidized lumiflavin hydrochloride hydrate: Comparison with the hydrogen bonding at the cofactor of flavoproteins

In order to examine the possibility of hydrogen bonding around the flavin ring, an X-ray diffraction study of the title compound was undertaken. Crystals of lumiflavin hydrochloride hydrate [2(C₁₃H₁₂N₄O₂) 4 HCl 7 H₂O] are triclinic, space group ,Z=2,a=11.064(1),b=17.903(1),c=9.891(1)Å, =111.9(6), -96.4(8), =91.6(7)°. We present the crystal structure of this compound and compare it with other flavin derivatives and with the structure of the active site of some flavoproteins.     

Structure of methylphenylhydrazone form of 2-(2-methylphenylazo)-1,3-indandione

The molecule crystallizes in a ketohydrazone tautomeric form. The tautomeric form is stabilized by a strong intramolecular hydrogen bond of 2.709(2) Å binding the 3-oxo to the nearest nitrogen atom in the azine chain. The compound crystallizes in the monoclinic space group P2_l/c witha=7.0470(4),b=11.3090(9),c=16.2250(4) Å, =90.310(3)°, V=1293.0(1) ų, Z=4,Dx=1.3576 g cm^–3 and (Cu-K)=7.03 cm^–1. The molecule is nearly planar not regarding the methyl group; the small deviations from planarity are indicative of intramolecular interactions between the phenylazo group and indandione group. Some of the bond lengths and angles found in the molecule are distorted due to resonance, -electron delocalization and strain. The relation between these chemical effects and structural results are discussed.     

Structure oftrans-difluorobis(1,3-propanediamine)chromium(III) perchlorate,trans-[Cr(N2C3H10)2F2](C104)

The title compound is monoclinic,M _r =337.8,P2₁/c-C _2h ⁵ (No. 14),a=5.508(2),b=13.944(6),c=18.238(5) Å,=95.99(3)°,V=1393.1(9) ų,Z=4,D _x =1.61 g cm^–3, (MoK)=0.71073 Å,F(000)=660.0,=10.3 cm^–1, finalR=0.051 for 2122 observed [I>3(I)] reflections. The two six-membered rings resulting from the coordination of the 1,3-propanediamine ligands to the chromium atom are in the chair conformation. The Cr-N and Cr-F distances average 2.085(4) and 1.876(3) Å, respectively.