TY - JOUR
T1 - Absolute configuration of (-)-myrtenal by vibrational circular dichroism
AU - Burgueño-Tapia, Eleuterio
AU - Zepeda, L. Gerardo
AU - Joseph-Nathan, Pedro
PY - 2010/7
Y1 - 2010/7
N2 - The VCD spectrum of the monoterpene (-)-myrtenal (1) was compared with theoretical spectra using ab initio density functional theory (DFT) calculations at the B3LYP/6-31G(d,p), B3LYP/6-31G+(d,p), B3LYP/6-311G+(d,p), B3LYP/DGDZVP, and B3PW91/DGTZVP levels of theory. Conformational analysis of 1 indicated that the lowest energy conformer was s-trans-C2-C10, which contributes more than 98.5% to the total conformational population regardless of the employed level of theory. The use of a recently developed confidence level algorithm demonstrated that VCD spectra calculated for the main conformer, using the indicated hybrid functionals and basis set, gave no significant changes, from where it follows that B3LYP/DGDZVP calculations provide a superior balance between computer cost and VCD spectral accuracy. The DGDZVP basis set demanded around a quarter the time than the 6-311G+(d,p) basis set while providing similar results. The spectral comparison also provided evidence that the levorotatory enantiomer of myrtenal has the 1R absolute configuration.
AB - The VCD spectrum of the monoterpene (-)-myrtenal (1) was compared with theoretical spectra using ab initio density functional theory (DFT) calculations at the B3LYP/6-31G(d,p), B3LYP/6-31G+(d,p), B3LYP/6-311G+(d,p), B3LYP/DGDZVP, and B3PW91/DGTZVP levels of theory. Conformational analysis of 1 indicated that the lowest energy conformer was s-trans-C2-C10, which contributes more than 98.5% to the total conformational population regardless of the employed level of theory. The use of a recently developed confidence level algorithm demonstrated that VCD spectra calculated for the main conformer, using the indicated hybrid functionals and basis set, gave no significant changes, from where it follows that B3LYP/DGDZVP calculations provide a superior balance between computer cost and VCD spectral accuracy. The DGDZVP basis set demanded around a quarter the time than the 6-311G+(d,p) basis set while providing similar results. The spectral comparison also provided evidence that the levorotatory enantiomer of myrtenal has the 1R absolute configuration.
KW - Absolute configuration
KW - Myrtenal
KW - Vibrational circular dichroism
UR - http://www.scopus.com/inward/record.url?scp=77954219095&partnerID=8YFLogxK
U2 - 10.1016/j.phytochem.2010.04.005
DO - 10.1016/j.phytochem.2010.04.005
M3 - Artículo
SN - 0031-9422
VL - 71
SP - 1158
EP - 1161
JO - Phytochemistry
JF - Phytochemistry
IS - 10
ER -