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GIAO DFT 13C/15N chemical shifts in regioisomeric structure determination of fused pyrazoles

✍ Scribed by Stefano Chimichi; Marco Boccalini; Alessandra Matteucci; Sergey V. Kharlamov; Shamil K. Latypov; Oleg G. Sinyashin

Publisher
John Wiley and Sons
Year
2010
Tongue
English
Weight
181 KB
Volume
48
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The combined use of two‐dimensional NMR correlation experiments and gauge including atomic orbital density functional theory in ^13^C NMR chemical shift (CS) calculations allowed reliable and simple structural determination of regioisomeric heterocyclic systems that originate from the reactions of acylquinolinones with substituted hydrazines. Moreover, the results of differential analysis between the calculated ^15^N NMR CSs for hypothetical structures and the experimental data of the title azaheterocyclic systems were even more advantageous with respect to ^13^C because there was no need for correlational analysis: structures of the regioisomeric compounds could be determined just by direct comparison. Copyright © 2010 John Wiley & Sons, Ltd.

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