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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
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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: s.grabowski@ikerbasque.org
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.
S.J.Grabowski, J. Phys. Chem. A 2011, 115, 12340–12347 S.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 2005 V. 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 bond often attributed to covalency of the hydrogen bond Reed, A.E.; Curtiss, L.A.; Weinhold, F. Chem.Rev. 1988, 88, 899-926. Sobczyk, L.; Grabowski, S.J.; Krygowski, T.M. Chem.Rev. 2005, 105, 3513-3560. Grabowski, S.J. Chem.Rev. 2011, 11, 2597-2625. 2. the rehybridization-promoted bond A-H strengthening. the increase of the s-character in the A-atom hybrid orbital of the A-H bond a consequence of Bent´s rule
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
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.
MP2/6-311++G(d,p) calculations F3CCl…OCH2 - XB F3CCl…HF - HB F3CCl…HMgH - XHeB F3CCl…H3O+ - CAHB(+) F3CCl…ClCH3 – DXB
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
Pol(%F) 79.3 S(%F) 24.2 Pol(%F) 77.6 S(%F) 20.7 Pol(%C) 50.4 S(%C) 43.0 Pol(%C) 47.9 S(%C) 41.1 Pol(%F) 78.6 S(%F) 23.3 Pol(%C) 49.8 S(%C) 42.7
Thank you for attention 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.