Premium
Synthesis of the Natural Product Building Block 5‐(3‐Bromophenyl)‐4‐hydroxy‐5‐methylhexan‐2‐one and its Chiral Characterization by Using Chiroptical Spectroscopy
Author(s) -
De Gussem Ewoud,
Cornelus Jelle,
Pieters Sam,
Van den Bossche Dries,
Van der Eycken Johan,
Herrebout Wouter,
Bultinck Patrick
Publication year - 2013
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.201300551
Subject(s) - absolute configuration , circular dichroism , chemistry , vibrational circular dichroism , enantiomer , density functional theory , optical rotatory dispersion , spectroscopy , chirality (physics) , computational chemistry , stereochemistry , physics , symmetry breaking , chiral symmetry breaking , nambu–jona lasinio model , quantum mechanics
Abstract The absolute configuration of 5‐(3‐bromophenyl)‐4‐hydroxy‐5‐methylhexan‐2‐one, an intermediate in the synthesis of various natural products, is assigned by using vibrational circular dichroism (VCD), electronic circular dichroism (ECD), and optical rotatory dispersion (ORD). Experimental spectra were compared to density functional theory (DFT) calculations of the molecule with known configuration. These three techniques independently confirm that the absolute configuration is ( S )‐5‐(3‐bromophenyl)‐4‐hydroxy‐5‐methylhexan‐2‐one, thus enabling us to assign the absolute configuration with high reliability. The reliability of the VCD analysis was assessed quantitatively by using the CompareVOA program. We found that, in cases in which the agreement between theory and experiment was very good, a value of 10 cm −1 for the triangular weighting function gave a more‐realistic discriminative power between enantiomers than the default value of 20 cm −1 .