Electron density topological analysis of hydrogen bonding in glucopyranose and hydrated glucopyranose.
Topological analysis of the electron density profiles and the atomic basin integration data for the most energetically favorable (4)C(1) and (1)C(4) conformers of beta-D-glucopyranose, calculated at the B3LYP/6-31+G(d), MPWlPW91/6-311+G(2d,p), and MP2/6-31+G(d) levels, demonstrates that intramolecular hydrogen bonding between adjacent ring OH groups does not occur in glucopyranose, given the need to demonstrate a bond critical point (BCP) of correct (3,-1) topology for such an interaction to be termed a hydrogen bond. On the other hand, pyranose ring OH groups separated by three, rather than just two, carbon atoms are able to form an intramolecular hydrogen bond similar in topological properties and geometry to that found for propane-1,3-diol. Vicinal, equatorial OH groups in the (4)C(1) conformer of glucopyranose are, however, able to form strong bidentate hydrogen bonds with water molecules in a cooperative manner, each water molecule acting simultaneously as both hydrogen bond donor and acceptor, and characterized by (3,-1) bond critical points with increased values for the electron density and the Laplacian of rho(r) compared to an isolated ethane-1,2-diol/water complex.
Klein
Roger A
RA
Institute for Physiological Chemistry, University of Bonn, 53115 Bonn, Germany. klein@institute.physiohem.uni-bonn.de
D004583:Electrons; D005947:Glucose / Q000031:analogs & derivatives* / Q000737:chemistry; D006860:Hydrogen Bonding; D008958:Models, Molecular; D011714:Pyrans / Q000737:chemistry*; D013055:Spectrophotometry, Infrared
D011714:Pyrans; D005947:Glucose