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Conformational analysis of N-Boc-N,O-isopropylidene-α-serinals. A combined DFT and NMR study

✍ Scribed by Alberto Avenoza; Jesús H. Busto; Francisco Corzana; Gonzalo Jiménez-Osés; Jesús M. Peregrina

Publisher
Elsevier Science
Year
2003
Tongue
French
Weight
571 KB
Volume
59
Category
Article
ISSN
0040-4020

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✦ Synopsis

This work describes an extensive conformational analysis of Garner's aldehyde and its a-methylated homologue-two important chiral building blocks that are widely used in organic synthesis. A combination of density-functional theory and NMR spectroscopy confirmed the existence of a dynamic equilibrium between two possible conformers of the carbamate group in these compounds. The calculated properties such as conformer populations and rotational barriers around the (CvO)-N bond are in good agreement with the experimental values. Finally, the dipole moments of the molecules appear to be a decisive factor in the stabilization of the conformers in solution.

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