Supporting Information from Sensing study of quinoxaline analogues with theoretical calculation, single-crystal X-ray structure and real application in commercial fruit juices

Single-crystal X-ray structures of dimeric quinoxaline aldehyde (QA), quinoxaline dihydrazone (DHQ) and HQNM (Goswami S <i>et al.</i> 2013 <i>Tetrahedron Lett.</i> <b>54</b>, 5075–5077. (doi:10.1016/j.tetlet.2013.07.051); Goswami S <i>et al.</i> 2014 <i>RSC Adv.</i> <b>4</b>, 20 922–20 926. (doi:10.1039/C4RA00594E); Goswami S <i>et al.</i> 2014 <i>New J. Chem.</i> <b>38</b>, 6230–6235. (doi:10.1039/C4NJ01498G) are reported along with the theoretical study. Among them, QA is not acting as an active probe, but DHQ and HQNM are serving as a selective and sensitive probe for the Fe<sup>3+</sup> cation and the Ni<sup>2+</sup> cation, respectively. DHQ can also detect the Fe<sup>3+</sup> in commercial fruit juices (grape and pomegranate).