E-2-Benzylidenebenzocycloalkanones. IV. Studies on transmission of substituent effects on 13C NMR chemical shifts of E-2-(X-benzylidene)-1-tetralones, and -benzosuberones. Comparison with the 13C NMR data of chalcones and E-2-(X-benzylidene)-1-indanones

Pál Perjési, Juha Linnanto, Erkki Kolehmainen, Erzsébet Osz, Elina Virtanen

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

Single substituent parameter (SSP) and dual substituent parameter (DSP) analyses were applied to study the transmission of substituent effects on selected 13C NMR chemical shifts of the cyclic chalcone analogues, E-2-(4′-X-benzylidene)-1-tetralones (2) and E-2-(4′-X-benzylidene)- 1-benzosuberones (3). In order to study how the geometry of the cyclic chalcone analogues affects the transmission of substituent effects similar investigations with the respective chalcones (4) were also performed. The results obtained earlier with the five-membered analogue E-2-(4′-X-benzylidene)-1-indanones (1) were also involved in the comparisons. Geometry optimization of the unsubstituted 1a, 2a, 3a and 4a as well as the substituted 2 and 3 was performed by ab initio quantum chemical calculations. Both SSP and DSP analyses reflected that resonance effects contribute more to the chemical shift of C-α (C2), while inductive effects primarily affect that of C-β (C10) of the enone moiety of all the four series. This latter effect, however, is far not as pronounced as that of the former one. It was found that DSP analysis data (ρF and ρR values) of transmission of substituent effects on the δC2 data can serve as a measure of choice to study the conformation (planarity) of the investigated enones in the four series.

Original languageEnglish
Pages (from-to)81-89
Number of pages9
JournalJournal of Molecular Structure
Volume740
Issue number1-3
DOIs
Publication statusPublished - Apr 25 2005

Keywords

  • C NMR
  • Chalcones
  • Conformational analysis
  • E-2-benzylidene-1-benzosuberones
  • E-2-benzylidene-1-teralones
  • Quantum chemical calculations
  • Transmission of substituent effects

ASJC Scopus subject areas

  • Analytical Chemistry
  • Spectroscopy
  • Organic Chemistry
  • Inorganic Chemistry

Fingerprint Dive into the research topics of 'E-2-Benzylidenebenzocycloalkanones. IV. Studies on transmission of substituent effects on <sup>13</sup>C NMR chemical shifts of E-2-(X-benzylidene)-1-tetralones, and -benzosuberones. Comparison with the <sup>13</sup>C NMR data of chalcones and E-2-(X-benzylidene)-1-indanones'. Together they form a unique fingerprint.

  • Cite this