scholarly journals Solid state and solution structural investigation of homoleptic tin(IV) alkoxide compounds. Part I. Sn(O—t-Bu)4 and [Sn(O—i-Pr)4•HO—i-Pr]2

1991 ◽  
Vol 69 (1) ◽  
pp. 121-129 ◽  
Author(s):  
Mark J. Hampden-Smith ◽  
Teresa A. Wark ◽  
Arnold Rheingold ◽  
John C. Huffman
Keyword(s):  
Solid State ◽  
Variable Temperature ◽  
Equilibrium Concentration ◽  
Molecular Structures ◽  
Monoclinic Crystal System ◽  
Monoclinic Crystal ◽  
Space Group ◽  
Crystal System ◽  
Reversible Dissociation ◽  
C Nmr

The crystal and molecular structures of Sn(O—t-Bu)4• and [Sn(O—i-Pr)4•HO—i-Pr]2 have been determined by single-crystal X-ray diffraction. Sn(O—t-Bu)4 crystallizes in the monoclinic crystal system with space group C2/c, where a = 17.382(6) Å, b = 8.742(2) Å, c = 15.518(5) Å, β = 116.44(1)°, Z = 4, and R = 2.5%. Sn(O—t-Bu)4 is monomeric in the solid state, with a distorted tetrahedral tin coordination environment. [Sn(O—i-Pr)4•HO—i-Pr]2 crystallizes in the monoclinic crystal system with space group P21/n, where a = 11.808(3) Å, b = 14.356(3) Å, c = 12.380(2) Å, β = 95.27(2)°, Z = 2, and R = 4.9%. [Sn(O—i-Pr)4•HO—i-Pr]2 exhibits an edge-shared, bi-octahedral structure in the solid state that is distorted due to the presence of asymmetric hydrogen bonding between axially coordinated alcohol ligands and an isopropoxide ligand.13C NMR and IR spectroscopic data have been recorded for Sn(O—t-Bu)4 and Sn(O—t-Bu-d9)4 to establish criteria for unambiguous identification of solution structures of tin(IV) alkoxides. It is demonstrated that the two-bond [Formula: see text] coupling constant is larger for terminal alkoxide ligands than for μ2-alkoxide bridges, and the ν(Sn—O) stretching frequency has been assigned. The dynamic solution behaviour of [Sn(O—i-Pr)4•HO—i-Pr]2 has been studied using variable temperature 1H and 13C NMR spectroscopy. The data obtained are consistent with a process that involves rapid reversible dissociation of isopropanol at room temperature. Upon cooling, the equilibrium concentration of the species with coordinated alcohol increases, and the molecule undergoes rapid intramolecular proton transfer (AG≠ < 11.9 kcalmol−1). Upon further cooling, the 13C NMR data are consistent with a solution structure analogous to that found in the solid state. Key words: tin, alkoxide, NMR, dynamic, structure.

The chemistry of copper(I) β-diketonate compounds. Part V. Syntheses and characterization of (β-diketonate)CuLn species where L = PBu3, PPh3, and PCy3; n = 1 and 2; crystal and molecular structures of (acac)Cu(PCy3), (tfac)Cu(PCy3), (hfac)Cu(PCy3), and (hfac)Cu(PCy3)2

1992 ◽  
Vol 70 (12) ◽  
pp. 2954-2966 ◽  
Author(s):  
H.-K. Shin ◽  
M. J. Hampden-Smith ◽  
E. N. Duesler ◽  
T. T. Kodas
Keyword(s):  
Solid State ◽  
Molecular Structures ◽  
Lewis Acidity ◽  
High Yield ◽  
Monoclinic Crystal System ◽  
X Ray Diffraction ◽  
Monoclinic Crystal ◽  
Space Group ◽  
Crystal System ◽  
Copper Coordination

The compounds (β-diketonate)Cu(PR3)n, where β-diketonate = 1,1,1,5,5,5-hexafluoroacetylacetonate, hfac; 1,1,1-trifluoroacetylacetonate, tfac; and acetylacetonate, acac; R = n-butyl (n-Bu), phenyl (Ph), and cyclohexyl (Cy); n = 1 and 2, have been prepared. The monotriorganophosphine adducts were prepared in high yield by the reaction of the sodium salt of the corresponding β-diketonate with [ClCu(PR3)] with elimination of sodium chloride. The bis(triorganophosphine) adducts were prepared by the reaction of (β-diketonate)Cu(PR3) with one equivalent of triorganophosphine. These species were characterized by 1H, 13C, and 31P NMR spectroscopy, FTIR spectroscopy, mass spectroscopy, and by combustion elemental analysis. Four examples were structurally characterized by single crystal X-ray diffraction in the solid state. (acac)CuPCy3 crystallizes in the triclinic crystal system, space group [Formula: see text], where a = 13.502(6) Ǻ, b = 13.691(6) Ǻ, c = 5.781(6) Ǻ, α = 71.05(3)°, β = 67.50(3)°, γ = 64.81(3)°, Z = 4, and R = 5.42%. (tfac)CuPCy3 crystallizes in the monoclinic crystal system, space group P21/n, where a = 9.639(3) Ǻ, b = 22.717(7) Ǻ, c = 12.045(5) Ǻ, β = 111.67(3)°, Z = 4, and R = 7.22%. (hfac)CuPCy3 crystallizes in the monoclinic crystal system, space group P21/c, where a = 9.870(2) Ǻ, b = 17.314(4) Ǻ, c = 15.586(3) Ǻ, β = 99.74(2)°, Z = 4, and R = 5.29%. (hfac)Cu(PCy3)2 crystallizes in the monoclinic crystal system, space group P21/n, where a = 13.645(6) Ǻ, b = 19.252(13) Ǻ, c = 16.875(9) Ǻ, β = 102.02(4)°, Z = 4, and R = 7.20%. The compounds (β-diketonate)Cu(PCy3) are all monomeric in the solid state and possess approximately trigonal-planar copper coordination environments, although (tfac)Cu(PCy3) is significantly distorted from trigonal geometry. The Cu—O bond distances are significantly different in this species. The compound (hfac)Cu(PCy3)2 is monomeric in the solid state and possesses a distorted tetrahedral copper coordination environment. The distortion is believed to be due to the large steric demands of the PCy3 ligands that result in long Cu—P bond distances of 2.251(3) and 2.277(3) Ǻ, a large P—Cu—P angle of 141.3(1)°, long Cu—O distances of 2.213(5) and 2.251(5) Ǻ, and a small O—Cu—O angle of 80.8(2)° compared to the corresponding values for (hfac)Cu(PCy3). No trends in Cu—O bond distances between the compounds can be discerned, within the limits of error on the data, that would clearly enable a comparison of thermodynamic parameters such as bond length – bond strength relationships as a function of the β-diketonate substituents. However, the spectroscopic data revealed a number of trends as a function of the β-diketonate substituents, including an increase of ν(C=O and ν(C=C) in the order acac < tfac < hfac, analogous to the increase in their Lewis acidity. An increase in shielding of the 31P resonance of the triorganophosphine ligands was observed in the order hfac < tfac < acac, consistent with expected inductive effects based on the electronegativity of the β-diketonate substituents.

Unexpected beauty and diversity in the structures of three homologous 4,5-dialkoxy-1-ethynyl-2-nitrobenzenes: the subtle interplay between intermolecular C—H...O hydrogen bonds and alkyl chain length

2017 ◽  
Vol 73 (10) ◽  
pp. 814-819 ◽  
Author(s):  
Shalisa M. Oburn ◽  
Eric Bosch
Keyword(s):  
Nmr Spectra ◽  
Alkyl Chain ◽  
Alkyl Chain Length ◽  
Monoclinic Crystal System ◽  
Monoclinic Crystal ◽  
Triclinic Crystal System ◽  
Space Group ◽  
X Ray ◽  
Crystal System ◽  
C Nmr

The synthesis, 1H and 13C NMR spectra, and X-ray structures are described for three dialkoxy ethynylnitrobenzenes that differ only in the length of the alkoxy chain, namely 1-ethynyl-2-nitro-4,5-dipropoxybenzene, C14H17NO4, 1,2-dibutoxy-4-ethynyl-5-nitrobenzene, C16H21NO4, and 1-ethynyl-2-nitro-4,5-dipentoxybenzene, C18H25NO4. Despite the subtle changes in molecular structure, the crystal structures of the three compounds display great diversity. Thus, 1-ethynyl-2-nitro-4,5-dipropoxybenzene crystallizes in the trigonal crystal system in the space group R{\overline 3}, with Z = 18, 1,2-dibutoxy-4-ethynyl-5-nitrobenzene crystallizes in the monoclinic crystal system in the space group P21/c, with Z = 4, and 1-ethynyl-2-nitro-4,5-dipentoxybenzene crystallizes in the triclinic crystal system in the space group P{\overline 1}, with Z = 2. The crystal structure of 1-ethynyl-2-nitro-4,5-dipropoxybenzene is dominated by planar hexamers formed by a bifurcated alkoxy sp-C—H...O,O′ interaction, while the structure of the dibutoxy analogue is dominated by planar ribbons of molecules linked by a similar bifurcated alkoxy sp-C—H...O,O′ interaction. In contrast, the dipentoxy analogue forms ribbons of molecules alternately connected by a self-complementary sp-C—H...O2N interaction and a self-complementary sp 2-C—H...O2N interaction. Disordered solvent was included in the crystals of 1-ethynyl-2-nitro-4,5-dipropoxybenzene and its contribution was removed during refinement.

scholarly journals Synthesis And Structural Characterization Of 1-Butyl-2,3-Dimethylimidazolium Bromide And Iodide

2007 ◽  
Vol 62 (6) ◽  
pp. 868-870 ◽  
Author(s):  
Johanna Kutuniva ◽  
Raija Oilunkaniemi ◽  
Risto S. Laitinen ◽  
Janne Asikkala ◽  
Johanna Kärkkäinen ◽  
...  
Keyword(s):  
Unit Cell ◽  
Monoclinic Crystal System ◽  
Monoclinic Crystal ◽  
Space Group ◽  
X Ray ◽  
Crystal System ◽  
H Nmr ◽  
Cell Dimensions ◽  
Unit Cell Dimensions

1-Butyl-2,3-dimethylimidazolium bromide {(bdmim)Br} (1) and iodide {(bdmim)I} (2) were prepared conveniently by the reaction of 1,2-dimethylimidazole and the corresponding 1-halobutane. The compounds were characterized by 1H and 13C{1H} NMR spectroscopy as well as by X-ray single crystal crystallography. 1 crystallizes in the monoclinic crystal system, space group P21/n, with Z = 4, and unit cell dimensions a = 8.588(2), b = 11.789(1), c = 10.737(2) Å, β = 91.62(3)°. Compound 2 crystallizes in the monoclinic crystal system, space group P21/c, with Z = 8, and unit cell dimensions a = 10.821(2), b = 14.221(3), c = 15.079(2) Å , β = 90.01(3)°. The lattices of the salts are built up of 1-butyl-2,3- dimethylimidazolium cations and halide anions. The cations of 1 form a double layer with the imidazolium rings stacked together due to π interactions. The Br− anions lie approximately in the plane of the imidazolium ring, and the closest interionic Br···H contacts span a range of 2.733(1) - 2.903(1) Å. Compound 2 shows no π stacking interactions. The closest interionic I···H contacts are 2.914(1) - 3.196(1) Å

Synthesis and Structural Characterization of N,N´- Dipropyl-N,N,N´,N´-tetramethyl-1,2- ethylenediammonium Dichloride and Dibromide

2011 ◽  
Vol 66 (7) ◽  
pp. 755-758
Author(s):  
Sari M. Närhi ◽  
Janne Asikkala ◽  
Jatta Kostamo ◽  
Marja K. Lajunen ◽  
Raija Oilunkaniemi ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Water Molecules ◽  
Monoclinic Crystal System ◽  
X Ray Diffraction ◽  
Monoclinic Crystal ◽  
Triclinic Crystal System ◽  
Space Group ◽  
X Ray ◽  
Crystal System

N,N´-Dipropyl-N,N,N´ ,N´-tetramethyl-1,2-ethylenediammonium dichloride (1) and dibromide (2) were prepared by the reaction of N,N,N´,N´-tetramethyl-1,2-ethylenediamine and the corresponding 1-halopropane. The structures of the compounds were characterized by single-crystal X-ray diffraction. 1 · 2H2O crystallizes in the triclinic crystal system, space group P1, with Z = 1, and 2 in the monoclinic crystal system, space group P21/c, with Z = 2. The crystal structures of the salts consist of discrete dications and halide anions. The packing in 1 · 2H2O consists of layers of cations with the chloride anions and water molecules forming hydrogen-bonded chains between the cation layers. In 2, the strongest H· · ·Br hydrogen bonds of 2.8138(6) and 2.8187(7) °A link the cations and anions into doublestranded chains. In both salts, cations and anions are also linked together by a further weak C-H· · ·Cl/Br hydrogen bonding network.

scholarly journals Synthesis and Catalytic Application of Two Mononuclear Complexes Bearing Diethylenetriamine Derivative Ligand

Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2101
Author(s):  
Chao Liu ◽  
Zhao Yang ◽  
Hao Guo ◽  
Yu-Cai Zhao
Keyword(s):  
Catalytic Mechanism ◽  
Aromatic Aldehydes ◽  
Monoclinic Crystal System ◽  
Henry Reaction ◽  
Monoclinic Crystal ◽  
Space Group ◽  
Crystal System ◽  
Catalytic Application ◽  
Composition And Structure ◽  
Elemental Analyses

Two mononuclear zero-dimensional Ni(II) and Zn(II) complexes bearing diethylenetriamine derivative ligand, namely [NiL(CH3COO)2(H2O)] (1) and [ZnL(CH3COO)2] (2) [L = N, N’-bis(2-hydroxybenzyl)diethylenetriamine], were synthesized under reflux conditions. The molecular composition and structure of the complexes were identified by IR, PXRD, elemental analyses, and single crystal X-ray diffraction. Complex 1 belongs to a monoclinic crystal system with the P21/n space group, and Complex 2 belongs to a monoclinic crystal system with the C2/c space group. The Henry reaction of nitromethane with aromatic aldehydes was explored with Complexes 1 and 2 as the catalyst. Results from the catalytic reaction revealed that the complexes displayed excellent catalytic activities under the optimized conditions and that the substrate scope of aromatic aldehydes could be extended to a certain extent. In addition, the possible catalytic mechanism of the Henry reaction was also deduced.

Synthesis, structure, and nonrigidity of Os4(CO)15, Os4(CO)13(PMe3)[P(OMe)3], and Os4(CO)14(CNBut)

1995 ◽  
Vol 73 (7) ◽  
pp. 1223-1235 ◽  
Author(s):  
Frederick W.B. Einstein ◽  
Victor J. Johnston ◽  
Andrew K. Ma ◽  
Roland K. Pomeroy
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectra ◽  
Energy Exchange ◽  
Variable Temperature ◽  
Carbonyl Cluster ◽  
Space Group ◽  
Exchange Processes ◽  
Nuclear Magnetic Resonance Spectra ◽  
Osmium Carbonyl ◽  
C Nmr

The binary carbonyl Os4(CO)15, 1, has been prepared by the addition of Os(CO)5 to Os3(CO)10(cyclooctene)2 at −15 °C. The related clusters Os4(CO)13(PMe3)[P(OMe)3], 2, and Os4(CO)14(CNBu′), 3, have been synthesized from Os4(CO)13(PMe3) and Os4(CO)15(CNBu′), respectively. The crystal structures of 1, 2, and 3 reveal similar planar metal skeletons with short (2.774 (1) − 2.793 (2) Å) and long (2.978 (2) − 3.019 (2) Å) peripheral Os—Os bonds; the hinge Os—Os bond in 1–3 ranges in length from 2.936 (2) to 2.948 (1) Å. The variable temperature 13C nuclear magnetic resonance spectra of 1 and 3 show that both are highly nonrigid in solution even at −120 °C. The mechanism of nonrigidity is believed to be an all-equatorial, merry-go-round carbonyl exchange. The variable temperature 13C nmr spectra of 2 indicate it is rigid on the nmr time scale in solution at −45 °C. Carbonyl exchange is, however, observed in the spectrum at −6 °C. From the mode of collapse of the signals it is believed that the lowest energy exchange processes in 3 involve axial-equatorial, merry-go-round CO exchanges in the two planes that each contain a short Os—Os bond. Crystallographic data for compound 1: space group C2/c; a = 12.802 (3) Å, b = 10.217 (3) Å, c = 16.380 (5) Å, β = 91.39 (2)°; R = 0.044, 1204 observed reflections. For compound 2: space group P21/c; a = 11.106 (7) Å, b = 16.931 (5) Å, c = 16.481 (5) Å, β = 97.71 (5)°; R = 0.051, 2117 observed reflections. For compound 3: space group P21/n; a = 11.747 (3) Å, b = 18.009 (5) Å, c = 12.448 (2) Å, β = 92.65 (2)°; R = 0.054, 2131 observed reflections. Keywords: osmium, carbonyl, cluster, nonrigidity.

Reactivity of diosmacycles: complementary syntheses and structure Of [(µ-η1,η2-CHCH2)OS2(CO)8][BF4]

1995 ◽  
Vol 73 (7) ◽  
pp. 1003-1009 ◽  
Author(s):  
R.G. Ball ◽  
Gong Y. Kiel ◽  
William A. Kiel ◽  
Josef Takats ◽  
Friedrich-Wilhelm Grevels
Keyword(s):  
Solid State ◽  
Traditional View ◽  
Cationic Complex ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray ◽  
Excellent Yield ◽  
Nmr Data ◽  
Hydride Abstraction ◽  
C Nmr

The vinyl-bridged cationic complex, [(µ-CHCH2)Os2(CO)8][BF4] (3), is obtained readily and in excellent yield either via hydride abstraction from octacarbonyl diosmacyclobutane, (µ-η1,η1-CH2CH2)Os2(CO)8 (1), or via protonation of octacarbonyl diosmacyclobutene, (µ-η1,η1-CHCH)Os2(CO)8 (2). It is argued that the 1H and 13C NMR data of complex 3 are consistent with the traditional view of bonding in µ-alkenyl complexes, involving substantial σ,π donation. The solid state X-ray structure of the complex lends support for this formulation. Complex 3 crystallizes in the orthorhombic space group, P212121, with a = 12.128(2) Å, b = 14.151(3) Å, c = 9.248(3) Å, V = 1587 Å3, and Z = 4. The final R and Rw values are 0.032 and 0.038, respectively. Keywords: µ-vinyl, diosmacycles, X-ray structure.

scholarly journals OLIGOMERIC CHROMIUM(III) POLICATION SPECIES-PILLARED LAYERED TETRATITANATES ANION

2010 ◽  
Vol 7 (1) ◽  
pp. 10-16 ◽  
Author(s):  
Hari Sutrisno ◽  
Endang Dwi Siswani
Keyword(s):  
Aqueous Solution ◽  
Ion Exchange ◽  
Room Temperature ◽  
Lattice Parameter ◽  
Bravais Lattice ◽  
Monoclinic Crystal System ◽  
Monoclinic Crystal ◽  
Crystal System ◽  
High Crystallinity

Intercalation of oligomeric chromium(III) polycation species in layered tetratitanates was prepared by three steps: 1) ion-exchange of H+ for K+ in potasium tetratitanates, 2) intercalation of n-alchylamine (n-propylamine, n-butylamine, n-amylamine, and n-hexylamine) compounds in layered hydrogen tetratitanates by adding an aqueous solution of  5M n-alchylamine to  hydogen titanates with stiring at room temperature,  and 3) intercalation of oligomeric chromium(III) polycation species by mixing butylamine-intercalated tetratitanates with an aqueous solution of CrCl3.6H2O at pH various. The procedure was carried out by Chimie Douce method. The results showed that all of n-alchylamine-intercalated tetratitanates crystallize on monoclinic crystal system with the Bravais lattice C. The hight intensity of the first peaks (200)  indicated that butylamine and amylamine-intercalated tetratitanates have a remarkably high crystallinity without impurities phase. The interlayered distance (d) and  the lattice parameter projected along a increase with increasing the amount of C-atoms in n-alchylamine. At pH=1.3, [CrCl(H2O)5]2+ or [CrCl2(H2O)4]+ species was pillared more efective in layered tetratitanates than [Cr(H2O)6]3+ spesies and just one spesies, Cr(H2O)6]3+ at  pH=1.7. On the contrary, [Cr(OH)(H2O)5]2+ or [Cr(OH)2(H2O)4]+ was  intercalated more effevtive than [Cr(H2O)6]3+ species  at pH=5.3.   Keywords: tetratitanates, intercalation, oligomeric chromium(III) species, Chimie Douce.

Effect of Meta-Substitution on Solid State Geometry of N-(Aryl)-2,2,2-trichloro-acetamides, 3-XC6H4NH-CO-CCl3 and 3,5-X2C6H3NH-CO-CCl3 (X = Cl, CH3)

2007 ◽  
Vol 62 (1-2) ◽  
pp. 91-100
Author(s):  
Basavalinganadoddy Thimme Gowda ◽  
Jozef Kožíšek ◽  
Ingrid Svoboda ◽  
Hartmut Fuess
Keyword(s):  
Solid State ◽  
Crystal Structures ◽  
Nitro Group ◽  
Room Temperature ◽  
Asymmetric Unit ◽  
Strong Electron ◽  
Space Group ◽  
Lattice Constants ◽  
Crystal System ◽  
Electron Withdrawing Group

The crystal structures of N-(meta-substituted phenyl)-2,2,2-trichloro-acetamides such as N- (3-methylphenyl)-2,2,2-trichloro-acetamide, 3-CH3C6H4NH-CO-CCl3 (3MPTCA); N-(3-chlorophenyl)- 2,2,2-trichloro-acetamide, 3-ClC6H4NH-CO-CCl3 (3CPTCA); N-(3,5-dimethylphenyl)- 2,2,2-trichloro-acetamide, 3,5-(CH3)2C6H3NH-CO-CCl3 (35DMPTCA) and N-(3,5-dichlorophenyl)- 2,2,2-trichloro-acetamide, 3,5-Cl2C6H3NH-CO-CCl3 (35DCPTCA) have been determined at room temperature. The crystal system, space group, formula units and lattice constants (Å ) of the new structures are: 3MPTCA: orthorhombic, Pbca, Z = 8, a = 12.3199(11), b = 8.9719(8), c = 20.2058(15); 3CPTCA: orthorhombic, Fdd2, Z =16, a=19.285(4), b=40.765(8), c=5.5920(11); 35DMPTCA: triclinic, P1̄, Z = 2, a = 8.994(4), b = 9.9890(10), c = 14.760(5), α = 79.56(2)°, β = 73.32(3)°, γ = 86.47(2)°; and 35DCPTCA: orthorhombic, Pbca, Z = 8, a = 22.485(5), b=10.738(2), c=10.028(3). The compound 35DMPTCA has two molecules in its asymmetric unit, similar to o-NO2-, m-NO2- and p-CH3-substituted phenyl-trichloro-acetamides, while 3MPTCA, 3CPTCA and 35DCPTCA have one molecule each in their asymmetric units. The analysis of data indicates that the substitution of a strong electron withdrawing group such as a nitro group into PTCA at ortho or meta positions has a significant effect on the crystal parameters.

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