Infrared and ¹³C NMR Spectral Studies of some Aryl Hydrazides: Assessment of Substituent Effects

Abstract

A series of some aryl hydrazides have been synthesized. These hydrazides purities were analyzed by physical constants and spectral data. The assigned spectral group frequencies were correlated with Hammett substituent constants and Swain-Lupton parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effect of substituents on the spectral group frequencies has been discussed

Effect of Substituent on the 13C NMR Chemical Shifts of Substituted 26-Member [2+2] Macrocyclic Compounds

“…Correlations with Lynch equation: In case of C 1 , there is a good correlation with (r = 0.998) appropriate SCS (S I ) values and slope b is 0.921, which discloses that the fixed substituent Y = C 25 H 23 N 2 O 4 , has little effect on the additivity of this shifts [20][21][22][23][24][25]. A good correlation exists between SCS of C 22' and S o with a correlation coefficient (r = 0.997) and the slope value (b = 0.966), indicating that the fixed substituent Y, has little effect on the additivity of these shifts [20][21][22][23][24][25]. A poor correlation exists between SCS of C 33' and S m with a correlation coefficient (r = 0.818) and the slope value (b = 0.599) discloses that the fixed substituent Y diminishes the substituent effect [26].…”

“…The 13 C chemical shifts of the carbon atoms of the macrocyclic compound series afford several reasonable correlations using Hammett substituent parameters eqn. 1 and the data are given in Table-3 [20][21][22][23][24][25][26].…”

Effect of Substituents on Phenazine Derivatives by Spectral Studies

“…The assigned the C=N stretches (cm -1 ) of the present investigation substituted phenazines were tabulated in Table 1. These data were correlated with Hammett substituent constants, F and R parameters [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. In this correlation, the Hammett equation was employed as,…”

“…The 13 C NMR chemical shifts of CN pyridine and phenazines moieties were assigned and are presented in Table 1. These chemical shifts were correlated with Hammett substituent constants, F and R parameters using single and multi-regression analysis [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. In these correlations, the Hammett equation was taken in the form as, δ = δ 0 + ρσ (2) Where δ 0 is the chemical shift of the corresponding parent compound.…”

“…Thirunarayanan and Sekar was studied the spectral qsar correlations in the pyrazoline derivatives [31]. The correlation study of infrared and 13 C-NMR chemical shifts of aryl hydrazides with Hammett substituent constants and F and R parameters were established by Thirunarayanan et al, [32] Mayavel et al, have investigated the spectral correlationslinearity of infrared and NMR spectral frequencies of carbazole imines with Hammett substituent constants, F and R parameters [33]. Sathiyendiran et al [34] have prepared some 2oxopropy diazenyl benzoic acids and studied the spectral correlation.…”