A computational investigation of the nitrogen-boron interaction in o-(N,N-dialkylaminomethyl)arylboronate systems

J Phys Chem A. 2010 Dec 2;114(47):12531-9. doi: 10.1021/jp1087674. Epub 2010 Nov 5.

Abstract

o-(N,N-Dialkylaminomethyl)arylboronate systems are an important class of compounds in diol-sensor development. We report results from a computational investigation of fourteen o-(N,N-dialkylaminomethyl)arylboronates using second-order Møller-Plesset (MP2) perturbation theory. Geometry optimizations were performed at the MP2/cc-pVDZ level and followed by single-point calculations at the MP2/aug-cc-pVDZ(cc-pVTZ) levels. These results are compared to those from density functional theory (DFT) at the PBE1PBE(PBE1PBE-D)/6-311++G(d,p)(aug-cc-pVDZ) levels, as well as to experiment. Results from continuum PCM and CPCM solvation models were employed to assess the effects of a bulk aqueous environment. Although the behavior of o-(N,N-dialkylaminomethyl) free acid and ester proved to be complicated, we were able to extract some important trends from our calculations: (1) for the free acids the intramolecular hydrogen-bonded B-O-H···N seven-membered ring conformers 12 and 16 are found to be slightly lower in energy than the dative-bonded N→B five-membered ring conformers 10 and 14 while conformers 13 and 17, with no direct boron-nitrogen interaction, are significantly higher in energy than 12 and 16; (2) for the esters where no intramolecular B-O-H···N bonded form is possible, the N→B conformers 18 and 21 are significantly lower in energy than the no-interaction forms 20 and 23; (3) H(2)O insertion reactions into the N→B structures 10, 14, 18, and 21 leading to the seven-membered intermolecular hydrogen-bonded B···OH(2)···N ring structures 11, 15, 19, and 22 are all energetically favorable.

Publication types

  • Research Support, N.I.H., Intramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Boron / chemistry*
  • Carbohydrates / chemistry
  • Chemistry, Physical / methods
  • Computer Simulation
  • Hydrogen Bonding
  • Models, Chemical
  • Models, Molecular
  • Molecular Conformation
  • Nitrogen / chemistry*
  • Quantum Theory
  • Software
  • Solvents / chemistry
  • Thermodynamics
  • Water / chemistry

Substances

  • Carbohydrates
  • Solvents
  • Water
  • Nitrogen
  • Boron