The Description of Non-Covalent Interactions in Terms of Bent´s Rule Sławomir J. Grabowski Faculty of Chemistry, University of the Basque Country UPV/EHU, and Donostia International Physics Center (DIPC), P.K. 1072, 20080 Donostia, Spain IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain e-mail: [email protected]
16
Embed
The Description of Non-Covalent Interactions in Terms of Bent´s Rule Sławomir J. Grabowski
The Description of Non-Covalent Interactions in Terms of Bent´s Rule Sławomir J. Grabowski Faculty of Chemistry, University of the Basque Country UPV/EHU, and Donostia International Physics Center (DIPC), P.K. 1072, 20080 Donostia, Spain - PowerPoint PPT Presentation
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
The Description of Non-Covalent Interactions in Terms of Bent´s Rule
Sławomir J. Grabowski
Faculty of Chemistry, University of the Basque Country UPV/EHU,and Donostia International Physics Center (DIPC),
P.K. 1072, 20080 Donostia, Spain
IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spaine-mail: [email protected]
Studies on non-covalent interactions
Rovira, C.; Novoa, J.J. Strength and Directianolity of the S…S Intermolecular Interactions, Chem. Eur. J. 1999, 5, 3689-3697
Braga, D.; Bazzi, C.; Grepioni, F.; Novoa, J.J. Electrostatic compression on non-covalent interactions : the case of π stacks involving ions, New.J.Chem. 1999, 23, 577.
Müller-Dethlefs , Hobza, P, Noncovalent Interactions: A Challenge for Experiment and Theory, Chem. Rev. 2000, 100, 143-167
Hobza, P.; Müller-Dethlefs, K. Non-Covalent Interactions, Theory and Experiment, Royal Society of Chemistry, Thomas Graham House, Science Park, Milton Road, Cambridge, 2010.
Lewis acid – Lewis base
Electron charge transfer
A-H+…-B hydrogen bond
A-H+…-H-B dihydrogen bond
A+…-H-B hydride bond
C-X+…-H-B halogen-hydride bond
C-X+…-B halogen bond
P.Lipkowski, S.J.Grabowski, J.Leszczynski J.Phys.Chem. A 2006, 110, 10296.
Hydrogen bondHB
A-H…B
Hydride bondHeB
A…H-B
Halogen bondXB
A-X…B
Dihydrogen bondDHB
A-H…H-B
Halogen-hydride bondXHeB
A-X…H-B
Dihalogen bondDXB
A-X…X-B
Halide bondXeB
A…X-B
S.J.Grabowski, J. Phys. Chem. A 2011, 115, 12340–12347S.J.Grabowski, J. Phys. Chem. A 2012, 116, 1838−1845
A-H…B hydrogen bond formation is a combination of two effects
F. Weinhold, C. Landis, Valency and Bonding, A Natural Bond Orbital Donor – Acceptor Perspective, Cambridge University Press 2005V. Alabugin, M. Manoharan, S. Peabody, F. Weinhold, J.Am.Chem.Soc. 2003, 125, 5973-5987 1. the hyperconjugative A-H bond weakening the charge transfer from the lone pair of B into the antibonding σ* orbital of the A-H bondoften attributed to covalency of the hydrogen bond
2. the rehybridization-promoted bond A-H strengthening.the increase of the s-character in the A-atom hybrid orbital of the A-H bonda consequence of Bent´s rule
A – H B
e e e
- + -
- - -
According to Bent´s rule
atoms maximize the s-character in hybrid orbitals aimed toward electropositive substituents and maximize their p-character in such orbitals aimed toward electronegative substituents
H. A. Bent, Chem.Rev. 1961, 61, 275-311
C Hal
greatest exchange repulsion
least exchange repulsionC Hal
electrostatic repulsion of nucleophiles
electrostatic attraction or small repulsionof nucleophiles
F.Zordan et al., J.Am.Chem.Soc. 127 (2005), 5979-5989.
Clark, T.; Hennemann, M.; Murray, J.S.; Politzer, P. J.Mol.Mod. 2007, 13, 291. Murray, J.; Concha, M.C.; Lane, P.; Hobza, P.; Politzer, P. J.Mol.Mod. 2008, 14, 699.
The chlorine – Lewis acid/Lewis base center distance (Cl…A(B), in Å), C-Cl bond length (Å), C-Cl…B(A) angle (degrees) as well as binding energy, Ebin (corrected for BSSE, in kcal/mol).
Eltrans (in milielectrons) - the amount of electrons transferring, Pol(%C) - the CCl proton donating bond polarization (% at C-atom), s(%C) - the percentage s-character in C orbital of the CCl proton donating bond
Financial support comes from Eusko Jaurlaritza (GIC 07/85 IT-330-07) and the Spanish Office for Scientific Research (CTQ2011-27374). Technical and human support provided by IZO-SGI SGIker (UPV/EHU, MICINN, GV/EJ, ESF) is gratefully acknowledged.