ChemInform Abstract: Ab initio Studies of Structural Features not Easily Amenable to Experiment. Part 41. Molecular Geometries of Hydrogen-Bonded Six-Membered Ring Structures of Glycerol

1985 ◽  
Vol 16 (31) ◽  
Author(s):  
C. VAN ALSENOY ◽  
V. J. KLIMKOWSKI ◽  
J. D. EWBANK ◽  
L. SCHAEFER
2006 ◽  
Vol 62 (6) ◽  
pp. 1112-1120 ◽  
Author(s):  
Valerio Bertolasi ◽  
Loretta Pretto ◽  
Valeria Ferretti ◽  
Paola Gilli ◽  
Gastone Gilli

The crystal structures of five β-enaminones are reported: (2Z)-3-(benzylamino)-1,3-diphenyl-prop-2-en-1-one, (2Z)-3-(benzylamino)-3-(2-hydroxyphenyl)-1-phenyl-prop-2-en-1-one, (2Z)-3-(benzylamino)-3-(4-methoxyphenyl)-1-(3-nitrophenyl)-prop-2-en-1-one, 2-{1-[(4-methoxyphenyl)amino]ethylidene}cyclohexene-1,3-dione and 2-{1-[(3-methoxyphenyl)amino]ethylidene}cyclohexene-1,3-dione. The structures were analysed and compared with those of similar compounds in order to establish which factors determine the range (2.53–2.72 Å) of N...O hydrogen-bond distances in intramolecularly hydrogen-bonded β-enaminones. It has been shown that, beyond electronic resonance-assisted hydrogen-bond effects modulated by substituents, the necessary requirements to produce very short N—H...O hydrogen bonding are steric intramolecular repulsions, including the embedding of an enaminonic C—C or C—N bond in an aliphatic six-membered ring. By considering the structural features it is possible to expect the strength of N—H...O hydrogen bonds adopted by specific β-enaminones.


2020 ◽  
Author(s):  
Frederik Haase ◽  
Gavin Craig ◽  
Mickaele Bonneau ◽  
kunihisa sugimoto ◽  
Shuhei Furukawa

Reticular framework materials thrive on designability, but unexpected reaction outcomes are crucial in exploring new structures and functionalities. By combining “incompatible” building blocks, we employed geometric frustration in reticular materials leading to emergent structural features. The combination of a pseudo C<sub>5</sub> symmetrical organic building unit based on a pyrrole core, with a C<sub>4</sub> symmetrical copper paddlewheel synthon led to three distinct frameworks by tuning the synthetic conditions. The frameworks show structural features typical for geometric frustration: self-limiting assembly, internally stressed equilibrium structures and topological defects in the equilibrium structure, which manifested in the formation of a hydrogen bonded framework, distorted and broken secondary building units and dangling functional groups, respectively. The influence of geometric frustration on the CO<sub>2</sub> sorption behavior and the discovery of a new secondary building unit shows geometric frustration can serve as a strategy to obtain highly complex porous frameworks.


2020 ◽  
Author(s):  
Frederik Haase ◽  
Gavin Craig ◽  
Mickaele Bonneau ◽  
kunihisa sugimoto ◽  
Shuhei Furukawa

Reticular framework materials thrive on designability, but unexpected reaction outcomes are crucial in exploring new structures and functionalities. By combining “incompatible” building blocks, we employed geometric frustration in reticular materials leading to emergent structural features. The combination of a pseudo C<sub>5</sub> symmetrical organic building unit based on a pyrrole core, with a C<sub>4</sub> symmetrical copper paddlewheel synthon led to three distinct frameworks by tuning the synthetic conditions. The frameworks show structural features typical for geometric frustration: self-limiting assembly, internally stressed equilibrium structures and topological defects in the equilibrium structure, which manifested in the formation of a hydrogen bonded framework, distorted and broken secondary building units and dangling functional groups, respectively. The influence of geometric frustration on the CO<sub>2</sub> sorption behavior and the discovery of a new secondary building unit shows geometric frustration can serve as a strategy to obtain highly complex porous frameworks.


1988 ◽  
Vol 181 (1-2) ◽  
pp. 169-178 ◽  
Author(s):  
Christian Van Alsenoy ◽  
Susan Kulp ◽  
Khamis Siam ◽  
V.Joseph Klimkowski ◽  
John D. Ewbank ◽  
...  

1989 ◽  
Vol 188 (1-2) ◽  
pp. 111-128 ◽  
Author(s):  
Lothar Schäfer ◽  
Khamis Siam ◽  
Johan D. Ewbank

2021 ◽  
Vol 23 (12) ◽  
pp. 7271-7279
Author(s):  
Anthony C. Legon

Radial P.E. functions of hydrogen-bonded complexes B⋯HF (B = N2, CO, PH3, HCN and NH3) have been calculated ab initio at the CCSD(T)(F12C)/cc-pVTZ-F12 level as a function of the hydrogen-bond length r(Z⋯H), where Z is the H-bond acceptor atom of B.


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