Substituent effect study on the experimental C-13 NMR chemical shifts of 3-(substituted phenyl)-3a,4,8,8a-tetrahydro-1,3-dioxepino[5,6-d] [1,2] isoxazoles


KARA Y. S. , Yalduz S.

JOURNAL OF MOLECULAR STRUCTURE, cilt.1193, ss.158-165, 2019 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 1193
  • Basım Tarihi: 2019
  • Doi Numarası: 10.1016/j.molstruc.2019.04.121
  • Dergi Adı: JOURNAL OF MOLECULAR STRUCTURE
  • Sayfa Sayıları: ss.158-165

Özet

Novel heterocyclic derivatives containing isoxazole ring were synthesized by the 1,3-dipolar cycloaddition reaction of substituted nitrile oxides with cis-4,7-dihydro-1,3-dioxepin in the present study. These 3(substituted phenyl)-3a,4,8,8a-tetrahydro-1,3-dioxepino[5,6-d] [1,2] isoxazole derivatives were characterized by their physical constants and IR, H-1 NMR, C-13 NMR and HRMS data. C-13 NMR spectra of studied molecules were measured in Deuterochloroform (CDCl3). The correlation analysis for the substituent-induced experimental C-13 NMR chemical shifts (delta, ppm) (SSC) of C=N, C4, C5, C7, C9 and C10 carbons of these isoxazole derivatives have been correlated with various Hammett substituent constants, and Swain-Lupton parameters using single (SSP) and multi-linear (DSP) regression analysis. Negative rho values were found for correlations of C=N, C4 and C5 carbons. The other carbons were found to have positive rho values for the electronic effect of substituent on C-13 NMR chemical shifts. (C) 2019 Elsevier B.V. All rights reserved.