scholarly journals Syntheses and crystal structures of the anhydride 4-oxatetracyclo[5.3.2.02,6.08,10]dodec-11-ene-3,5-dione and the related imide 4-(4-bromophenyl)-4-azatetracyclo[5.3.2.02,6.08,10]dodec-11-ene-3,5-dione

2020 ◽  
Vol 76 (8) ◽  
pp. 1311-1315
Author(s):  
Andrew Hulsman ◽  
Isabel Lorenzana ◽  
Theodore Schultz ◽  
Breezy Squires ◽  
Brock A. Stenfors ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Functional Group ◽  
Lone Pair ◽  
Ring System ◽  
Private Communication ◽  
Bond Lengths ◽  
Imide Ring ◽  
Non Covalent Interactions ◽  
Covalent Interactions

The syntheses and crystal structures of the two title compounds, C11H10O3 (I) and C17H14BrNO2 (II), both containing the bicyclo[2.2.2]octene ring system, are reported here [the structure of I has been reported previously: White & Goh (2014). Private Communication (refcode HOKRIK). CCDC, Cambridge, England]. The bond lengths and angles of the bicyclo[2.2.2]octene ring system are similar for both structures. The imide functional group of II features carbonyl C=O bond lengths of 1.209 (2) and 1.210 (2) Å, with C—N bond lengths of 1.393 (2) and 1.397 (2) Å. The five-membered imide ring is nearly planar, and it is positioned exo relative to the alkene bridgehead carbon atoms of the bicyclo[2.2.2]octene ring system. Non-covalent interactions present in the crystal structure of II include a number of C—H...O interactions. The extended structure of II also features C—H...O hydrogen bonds as well as C—H...π and lone pair–π interactions, which combine together to create supramolecular sheets.

scholarly journals Crystal structures ofp-substituted derivatives of 2,6-dimethylbromobenzene with ½ ≤Z′ ≤ 4

2016 ◽  
Vol 72 (12) ◽  
pp. 1762-1767
Author(s):  
Angélica Navarrete Guitérrez ◽  
Gerardo Aguirre Hernández ◽  
Sylvain Bernès
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Crystal Structures ◽  
Functional Group ◽  
Molecular Symmetry ◽  
Asymmetric Unit ◽  
Structure Feature ◽  
Non Covalent Interactions ◽  
Derivatives Of ◽  
Covalent Interactions

The crystal structures of four bromoarenes based on 2,6-dimethylbromobenzene are reported, which are differentiated according the functional groupXplacedparato the Br atom:X= CN (4-bromo-3,5-dimethylbenzonitrile, C9H8BrN), (1),X= NO2(2-bromo-1,3-dimethyl-5-nitrobenzene, C8H8BrNO2), (2),X= NH2(4-bromo-3,5-dimethylaniline, C8H10BrN), (3) andX= OH (4-bromo-3,5-dimethylphenol, C8H9BrO), (4). The content of the asymmetric unit is different in each crystal,Z′ = ½ (X= CN),Z′ = 1 (X= NO2),Z′ = 2 (X= NH2), andZ′ = 4 (X= OH), and is related to the molecular symmetry and the propensity ofXto be involved in hydrogen bonding. In none of the studied compounds does the crystal structure feature other non-covalent interactions, such as π–π, C—H...π or C—Br...Br contacts.

scholarly journals Crystal structure of dibromidobis(1,3-dibenzyl-1,3-diazinan-2-one-κO)cobalt(II)

2015 ◽  
Vol 71 (9) ◽  
pp. m160-m161
Author(s):  
Eduard Rais ◽  
Ulrich Flörke ◽  
René Wilhelm
Keyword(s):  
Crystal Structure ◽  
Rotation Axis ◽  
Title Complex ◽  
Dihedral Angles ◽  
Asymmetric Unit ◽  
Bond Lengths ◽  
Non Covalent Interactions ◽  
Van Der Waals Radii ◽  
Covalent Interactions ◽  
Axis Passing

The unit cell of the title complex, [CoBr2(C18H20N2O)2], contains 1.5 formula units per asymmetric unit with one molecule sitting on a general site and a second one halved by a crystallographic twofold rotation axis passing through the CoIIcation. Both CoIIatoms are coordinated in a distorted tetrahedral manner by two Br−ligands and two O atoms of the pyrimidinone (OPyr) groups. The Br—Co—Br coordination angles are similar [115.46 (4) and 115.20 (5)°], while the O—Co—O angles differ slightly more [102.26 (18) and 98.1 (2)°]. Similarly, the Co—Br bond lengths are almost identical [2.3721 (9), 2.3757 (10) and 2.3809 (10) Å], with a larger difference between the Co—O bond lengths [1.929 (4), 1.926 (4) and 1.955 (4) Å]. The three independent OPyr groups present envelope conformations, with three C and two N atoms lying in well defined planes with maximum deviations from the least-squares planes of 0.047, 0.031 and 0.036 Å, and the external-most C atoms protruding by 0.654 (6), 0.643 (7) and 0.656 (6) Å out of the planes. The dihedral angles between the planar fractions of the OPyr planes are 50.5 (1)° for the nonsymmetric molecule and 49.7 (1)° for the symmetric one. Non-covalent interactions are of the C—H...Br type and they are weak, hardly shorter than van der Waals radii, with an H...Br distance range of 3.00–3.04 Å. The intermolecular interactions define chains parallel to [101].

scholarly journals Comparison of molecular structures of cis-bis[8-(dimethylphosphanyl)quinoline]nickel(II) and -platinum(II) complex cations

2020 ◽  
Vol 76 (12) ◽  
pp. 1813-1817
Author(s):  
Masatoshi Mori ◽  
Takayoshi Suzuki
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Steric Hindrance ◽  
Molecular Structures ◽  
Coordination Geometry ◽  
Donor Group ◽  
Bending Deformation ◽  
Bond Lengths ◽  
Square Planar ◽  
Chelate Ligands

The crystal structures of the complexes (SP-4-2)-cis-bis[8-(dimethylphosphanyl)quinoline-κ2 N,P]nickel(II) bis(perchlorate) nitromethane monosolvate, [Ni(C11H12NP)2](ClO4)2·CH3NO2 (1), and (SP-4-2)-cis-bis[8-(dimethylphosphanyl)quinoline-κ2 N,P]platinum(II) bis(tetrafluoroborate) acetonitrile monosolvate, [Pt(C11H12NP)2](BF4)2·C2H3N (2), are reported. In both complex cations, two phosphanylquinolines act as bidentate P,N-donating chelate ligands and form the mutually cis configuration in the square-planar coordination geometry. The strong trans influence of the dimethylphosphanyl donor group is confirmed by the Ni—N bond lengths in 1, 1.970 (2) and 1.982 (2) Å and, the Pt—N bond lengths of 2, 2.123 (4) and 2.132 (4) Å, which are relatively long as compared to those in the analogous 8-(diphenylphosphanyl)quinoline complexes. Mutually cis-positioned quinoline donor groups would give a severe steric hindrance between their ortho-H atoms. In order to reduce such a steric congestion, the NiII complex in 1 shows a tetrahedral distortion of the coordination geometry, as parameterized by τ4 = 0.199 (1)°, while the PtII complex in 2 exhibits a typical square-planar coordination geometry [τ4 = 0.014 (1)°] with a large bending deformation of the ideally planar Me2Pqn chelate planes. In the crystal structure of 2, three F atoms of one of the BF4 − anions are disordered over two sets of positions with refined occupancies of 0.573 (10) and 0.427 (10).

scholarly journals Darstellung und Kristallstruktur von K2Sn2S5 und K2Sn2Se5 / Preparation and Crystal Structure of K2Sn2S5 and K2Sn2Se5

1992 ◽  
Vol 47 (2) ◽  
pp. 197-200 ◽  
Author(s):  
Kurt O. Klepp
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Structure Type ◽  
Slow Cooling ◽  
Bond Lengths ◽  
Trigonal Bipyramidal ◽  
Equatorial Bond ◽  
Binary Compounds ◽  
R Factors ◽  
Distorted Trigonal Bipyramidal

K2Sn2S5 and K2Sn2Se5 were prepared by reacting stoichiometric powdered mixtures of the binary compounds K2S or K2Se with Sn and the corresponding chalcogen at 1070 K, followed by slow cooling of the melt. The two compounds are isostructural and crystallize with the Tl2Sn2S5 structure type, s.g. C 2/c, Z = 4 with a = 11.072(5) Å, b = 7.806(3)Å, c = 11.517(5)Å, β = 108.43(2)° for K2Sn2S5 and a = 11.613(5)Å, b = 8.189(3) Å, c = 11,897(6) Å, β = 108.28(2)° for K2Sn2Se5. The crystal structures were refined to conventional R-factors of 0.032 and 0.031, respectively. Sn-atoms are in a distorted trigonal-bipyramidal chalcogen coordination. The average equatorial bond lengths are Sn -S: 2.427 Å and Sn -Se: 2.552 Å , the axial ones are Sn -S: 2.600 Å and Sn -Se: 2.774 Å.

scholarly journals Synthesis, crystal structure, and non-covalent interactions in ethyl 4-hydrazinobenzoate hydrochloride

2019 ◽  
Vol 1177 ◽  
pp. 363-370 ◽  
Author(s):  
Jelem Restrepo ◽  
Christopher Glidewell ◽  
Néstor Cubillán ◽  
Ysaias Alvarado ◽  
Necmi Dege ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Non Covalent Interactions ◽  
Covalent Interactions

GRX: a program to search the CSD for functional group exchanges

2005 ◽  
Vol 38 (4) ◽  
pp. 694-696 ◽  
Author(s):  
Jacco van de Streek ◽  
Sam Motherwell
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Functional Group ◽  
Cambridge Structural Database ◽  
Structural Database

In order to establish the effect of exchanging one functional group by another on the crystal structure, one would like to be able to search the Cambridge Structural Database for all pairs of crystal structures where this substitution has been made. A program calledGRX(group exchange) was written for that purpose.

scholarly journals Functional group interaction profiles: a general treatment of solvent effects on non-covalent interactions

2020 ◽  
Vol 11 (17) ◽  
pp. 4456-4466 ◽  
Author(s):  
Mark D. Driver ◽  
Mark J. Williamson ◽  
Joanne L. Cook ◽  
Christopher A. Hunter
Keyword(s):  
Free Energy ◽  
Solvent Effects ◽  
Functional Group ◽  
Group Interaction ◽  
General Treatment ◽  
Effect Of Solvent ◽  
Non Covalent Interactions ◽  
Covalent Interactions ◽  
Quantitative Tool

Functional group interaction profiles are a quantitative tool for predicting the effect of solvent on the free energy changes associated with non-covalent interactions.

Lewis-Base Adducts of Group 11 Metal(I) Compounds. LIX. Crystal Structure Determinations of Tetrakis(trimethylphosphine)copper(I) Halides and Tetrakis(triphenylphosphine)-copper(I) and -silver(I) Hexafluorophosphates

1990 ◽  
Vol 43 (10) ◽  
pp. 1697 ◽  
Author(s):  
GA Bowmaker ◽  
PC Healy ◽  
LM Engelhardt ◽  
JD Kildea ◽  
BW Skelton ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Crystal Structures ◽  
Lewis Base ◽  
X Ray Diffraction ◽  
Coordination Environment ◽  
X Ray ◽  
Bond Lengths ◽  
Cu Complex ◽  
Structure Determinations

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.

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