Water Extract of Rice Straw Ash: Experimental Design and Evaluation of Their Activity in the Hydrothiolation Reaction

Water Extract of Rice Straw Ash (WERSA) has attracted special attention in several areas of chemistry since they have been considered an alternative tool for green processes. Hence, the characterization of ashes and extract of this biomass are fundamental to figure out their particular applicability in a wide range of transformations. In this regard, herein we have characterized the ashes of rice straw (RSA) and its respective aqueous extract using Inductively Coupled Plasma Optical Emission Spectrometry and x-ray fluorescence. Noteworthy, we have investigated the effect of the metals from WERSA on the hydrothiolation of phenylacetylene employing ANOVA response, coefficient of determination, linear regression model as well as Fischer Test. Based on all these studies, it was found that calcium is the most important metal for the hydrothiolation reaction when compared to other metals present in the WERSA. Thus, it was also possible to propose a plausible reaction mechanism for the hydrothiolation of alkynes. In addition, the chemistry described herein might represent a new eco-friendly tendency for the organochalcogen field. Graphic Abstract