Substituent effect study on experimental 13C NMR chemical shifts of (3-(substituted phenyl)-cis-4,5-dihydroisoxazole-4,5-diyl)bis(methylene)diacetate derivatives

• Negative ρ values were found for at CO(C18), CN, C4, C12, C16 and C21 carbons for SSP (single substituent parameter) and DSP (dual substituent parameter) analysis.
• Positive ρ values were found for at C5 carbon with same analyses methods.

Eleven novel (3-(substituted phenyl)-cis-4,5-dihydroisoxazole-4,5-diyl)bis(methylene) diacetate derivatives were synthesized in the present study. These dihydroisoxazole derivatives were characterized by IR, 1H NMR, 13C NMR and elemental analyses. Their 13C NMR spectra were measured in Deuterochloroform (CDCl3). The correlation analysis for the substituent-induced chemical shift (SCS) with Hammett substituent constant (σ), inductive substituent constant (σI), different of resonance substituent constants (σR, σRo) and Swain–Lupton substituent parameters (F, R) were performed using SSP (single substituent parameter), and DSP (dual substituent parameter) methods, as well as single and multiple regression analysis. From the result of regression analysis, the effect of substituent on the 13C NMR chemical shifts was explained.

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