The Study On Solvent Effects Of Progesterone Etal Steroids Species By Ftir Spectroscopy

Infrared spectra of carbonyl stretching vibration frequencies of progesterone, androsta-1,4-diene-3,17-dione,5alpha-androstane-3,17-dione,trenbolone acetate, acetophenone were measured in single and binary mixture solvents,respectively.The solvent effects have been investigated based on the principles of variability for carbonyl bands.In single solvent systems,the frequencies of the carbonyl stretching vibrations of the five samples were correlated with solvent empirical parameter equations,which include single empirical parameters and multiparameter approaches.The single empirical parameters were solvent acceptor number AN, Kirkwood-Bauer-Magat(KBM)relationship,Brownstein's solvent parameter S, Dimroth's solvent parameter E_T(30)and linear Gibbs energy equation(LFE)proposed by Schleyer etal,and the multiparameter approaches were Swain's two-parameter treatment of solvent effects and linear solvation energy relationships(LSER).The suitability of the above parameter equations have been discussed and some solvent parameters have been modified in the paper.In binary solvent systems,the affects between the changes of solvent concentrations and solute-solvent interactions were studied.The binary solvent systems were composed of polar solvents contained more active hydrogen such as chloroform and alcohols,or the solvents containedÏ€or lone electrons of heteroatoms such as tetrachloromethane,benzene,toluene,tetrahydrofuran and 1,4-dioxane, and non-polar solvents such as cyclo-hexane.The binary solvent systems are eight categories included benzene/cyclo-hexane(C₆H₆/c-C₆H₁₂), toluene/cyclo-hexane(C₆H₅CH₃/c-C₆H₁₂),tetrahydrofuran/cyclo-hexane (C₄H₈O/c-C₆H₁₂),1,4-dioxane/cyclo-hexane(1,4-C₄H₈O₂/c-C₆H₁₂), dichloromethane/cyclo-hexane(CH₂Cl₂/c-C₆H₁₂),chloroform/cyclo-hexane(CHCl₃/ c-C₆H₁₂),cyclo-hexane/alcohol(c-C₆H₁₂/ROH)etal.It showed that there are all kinds of the band formations for the infrared stretching vibration frequencies of carbonyls in different chemical environment in five compounds in binary solvent systems.The assignments ofν(C=O)of the compounds in different solvent systems were discussed in detail.For example,the dipolar-inductive dipolar interaction in C₆H₆/c-C₆H₁₂;the 1:1 and 1:2 hydrogen bonding formed between the carbonyl of progesterone and chloroform/cyclo-hexane in the binary system;the interaction between the carbonyl and the associated alcohols or the hydrogen bonding between the carbonyl and non-associated alcohols;and the 1:2 hydrogen bonding formed between the carbonyl of steroids and alcohols etal.Comparisons were drawn for the solvent sensitivities ofν(C=O)of progesterone vs.the mole fraction of solvents for acetophenone and 5α-androstan-3,17-dione in chloroform/cyclo-hexane binary systems,respectively.It was suggested that the more stably the structure of carbonyl group is,the more the solvent sensitivity ofν(C=O)becomes.