A synthetic library of allylmethoxyphenyl esters: spectral characterization and gas chromatographic behavior

A recent identification of eugenyl (allylmethoxyphenyl) esters as Anthemis segetalis Ten. (Asteraceae) essential oil constituents, accomplished by means of organic synthesis, motivated us to expand the existing synthetic library with an aim to examine the generality of structure‐chromatographic property relationships within this series of volatiles. Herein, the design, synthesis, gas–chromatographic and spectral characterization of members of a library of 85 allylmethoxyphenyl esters (64 are completely new) were described. Analysis of experimentally obtained RI data showed that esters of the same acid and different allylmethoxyphenols always elute in the same order from an apolar gas chromatography (DB‐5MS) column: 2‐allyl‐6‐methoxyphenyl < 2‐allyl‐3‐methoxyphenyl < 2‐allyl‐5‐methoxyphenyl < 2‐allyl‐4‐methoxyphenyl < 4‐allyl‐2‐methoxyphenyl esters. Based on the obtained RI values, several quantitative structure–property relationship models were built up that correlated several easily available parameters (e.g. Wiener [WI], Balaban [BI], and molecular topological [MTI] indices) of the mentioned esters and their RI data. The generated various quantitative structure–property relationships models (equations that predict RIs of esters of different regioisomers of allylmethoxyphenols with the same acids and the ones that predict RIs of esters of different acids with the same allylmethoxyphenols) were tested on data of previously known related esters. RI data of esters of allylmethoxyphenol regioisomers could be successfully predicted based on 1D topological indices, such as the Balaban, Wiener, and molecular topological indices. Together with RI and MS data accumulated in this work, these models represent a new and simple tool for the identification of allylmethoxyphenyl esters that might potentially represent new or rare natural products.