Synthesis and molecular structures of a rhoda-lactone and its alkylation product; insertion of a pendant alkyne into a rhodium–hydrogen bond

1988 ◽  
pp. 996-998 ◽  
Author(s):  
Todd B. Marder ◽  
Dominic M.-T. Chan ◽  
William C. Fultz ◽  
David Milstein
Keyword(s):  
Hydrogen Bond ◽  
Molecular Structures ◽  
Alkylation Product

Molecular Structures of Ten Ionic Hydrogen Bond-mediated Anhydrous tert-butylammonium Salts From Different Carboxylic Acids

2021 ◽  
pp. 131917
Author(s):  
Xuejuan Yang ◽  
Yanhong Zhu ◽  
Xinlei Chen ◽  
Xingjun Gao ◽  
Shouwen Jin ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Carboxylic Acids ◽  
Molecular Structures

scholarly journals Crystal structures of butyl 2-amino-5-hydroxy-4-(4-nitrophenyl)benzofuran-3-carboxylate and 2-methoxyethyl 2-amino-5-hydroxy-4-(4-nitrophenyl)benzofuran-3-carboxylate

2019 ◽  
Vol 75 (6) ◽  
pp. 880-887 ◽  
Author(s):  
Rosita Diana ◽  
Angela Tuzi ◽  
Barbara Panunzi ◽  
Antonio Carella ◽  
Ugo Caruso
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Hydrogen Bonds ◽  
Molecular Structures ◽  
Antitumoral Activity ◽  
Space Group ◽  
One Dimensional ◽  
Axis Direction ◽  
Hydrogen Bonding Pattern ◽  
Butyl Group

The title benzofuran derivatives 2-amino-5-hydroxy-4-(4-nitrophenyl)benzofuran-3-carboxylate (BF1), C19H18N2O6, and 2-methoxyethyl 2-amino-5-hydroxy-4-(4-nitrophenyl)benzofuran-3-carboxylate (BF2), C18H16N2O7, recently attracted attention because of their promising antitumoral activity. BF1 crystallizes in the space group P\overline{1}. BF2 in the space group P21/c. The nitrophenyl group is inclined to benzofuran moiety with a dihedral angle between their mean planes of 69.2 (2)° in BF1 and 60.20 (6)° in BF2. A common feature in the molecular structures of BF1 and BF2 is the intramolecular N—H...Ocarbonyl hydrogen bond. In the crystal of BF1, the molecules are linked head-to-tail into a one-dimensional hydrogen-bonding pattern along the a-axis direction. In BF2, pairs of head-to-tail hydrogen-bonded chains of molecules along the b-axis direction are linked by O—H...Omethoxy hydrogen bonds. In BF1, the butyl group is disordered over two orientations with occupancies of 0.557 (13) and 0.443 (13).

Bis(2-nitrophenyl) selenide, bis(2-aminophenyl) selenide and bis(2-aminophenyl) telluride: structural and theoretical analysis

2021 ◽  
Vol 77 (6) ◽  
Author(s):  
Raju Saravanan ◽  
Harkesh B. Singh ◽  
Ray J. Butcher
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Weak Interactions ◽  
Intermolecular Hydrogen Bond ◽  
Three Dimensional ◽  
Molecular Structures ◽  
Aim Analysis ◽  
Hydrogen Bond Interaction ◽  
Dimensional Array ◽  
Pyramidal Geometry

Three organoselenium and organotellurium compounds containing ortho substitutents, namely, bis(2-nitrophenyl) selenide, C12H8N2O4Se, 2, bis(2-aminophenyl) selenide, C12H12N2Se, 3, and bis(2-aminophenyl) telluride, C12H12N2Te, 7, have been investigated by both structural and theoretical methods. In the structures of all three compounds, there are intramolecular contacts between both Se and Te with the ortho substituents. In the case of 2, this is achieved by rotation of the nitro group from the arene plane. For 3, both amino groups exhibit pyramidal geometry and are involved in intramolecular N—H...Se interactions, with one also participating in intermolecular N—H...N hydrogen bonding. While 3 and 7 are structurally similar, there are some significant differences. In addition to both intramolecular N—H...Te interactions and intermolecular N—H...N hydrogen bonding, 7 also exhibits intramolecular N—H...N hydrogen bonding. In the packing of these molecules, for 2, there are weak intermolecular C—H...O contacts and these, along with the O...N interactions mentioned above, link the molecules into a three-dimensional array. For 3, in addition to the N—H...N and N—H...Se interactions, there are also weak intermolecular C—H...Se interactions, which also link the molecules into a three-dimensional array. On the other hand, 7 shows intermolecular N—H...N interactions linking the molecules into R 2 2(16) centrosymmetric dimers. In the theoretical studies, for compound 2, AIM (atoms in molecules) analysis revealed critical points in the Se...O interactions with values of 0.017 and 0.026 a.u. These values are suggestive of weak interactions present between Se and O atoms. For 3 and 7, the molecular structures displayed intramolecular, as well as intermolecular, hydrogen-bond interactions of the N—H...N type. The strength of this hydrogen-bond interaction was calculated by AIM analysis. Here, the intermolecular (N—H...N) hydrogen bond is stronger than the intramolecular hydrogen bond. This was confirmed by the electron densities for 3 and 7 [ρ(r) = 0.015 and 0.011, respectively].

Systematic studies on benzimidazole derivatives: Molecular structures and their hydrogen bond networks formation toward proton transfer efficiency

2011 ◽  
Vol 196 (15) ◽  
pp. 6144-6152 ◽  
Author(s):  
Autchara Pangon ◽  
Puripong Totsatitpaisan ◽  
Priew Eiamlamai ◽  
Kimiko Hasegawa ◽  
Mikio Yamasaki ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Proton Transfer ◽  
Molecular Structures ◽  
Transfer Efficiency ◽  
Benzimidazole Derivatives ◽  
Hydrogen Bond Networks

Different acid–base behaviour of a pyrazole and an isoxazole with organic acids: crystal and molecular structures of the salt 3-(4-fluorophenyl)-1H-pyrazolium 2,4,6-trinitrophenolate and of the cocrystal 4-amino-N-(3,4-dimethyl-1,2-oxazol-5-yl)benzenesulfonamide–3,5-dinitrobenzoic acid (1/1)

2016 ◽  
Vol 72 (8) ◽  
pp. 612-618
Author(s):  
Marisiddaiah Girisha ◽  
Hemmige S. Yathirajan ◽  
Jerry P. Jasinski ◽  
Christopher Glidewell
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Molecular Structures ◽  
Hydrogen Bond Donor ◽  
Hydrogen Bond Acceptor ◽  
Form Complex ◽  
Carbocyclic Rings ◽  
Molecular Components ◽  
Related Compounds

Pyrazole and isoxazole rings differ only in the notional replacement of a potential hydrogen-bond-donor NH unit in pyrazole by a potential hydrogen-bond-acceptor O atom in isoxazole. It is thus of interest to compare the hydrogen-bonding characteristics of these rings. (4-Fluorophenyl)pyrazole undergoes protonation in the presence of 2,4,6-trinitrophenol to yield the salt 3-(4-fluorophenyl)-1H-pyrazolium 2,4,6-trinitrophenolate, C9H8FN2+·C6H2N3O7−, (I), whereas there is no proton transfer between 4-amino-N-(3,4-dimethyl-1,2-oxazol-5-yl)benzenesulfonamide and 3,5-dinitrobenzoic acid, whose reaction gives the 1:1 cocrystal, C11H13N3O3S·C7H4N2O6, (II). The bond lengths in salt (I) provide evidence for aromatic-type delocalization in the pyrazolium ring and for extensive delocalization of the negative charge into the ring of the trinitrophenolate anion. The O atoms of one of the nitro groups in the trinitrophenolate anion are disordered over two sets of atomic sites having occupancies of 0.571 (6) and 0.429 (6), but all of the other substituents on the carbocyclic rings are fully ordered. The ions in salt (I) are linked by an extensive series of N—H...O hydrogen bonds to form a three-dimensional framework structure, and in cocrystal (II), the molecular components are linked by a combination of O—H...N and N—H...O hydrogen bonds to form complex bilayers. Comparisons are made with some related compounds.

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