Green Chemistry’s Contribution to the Kamal Qureshi Protocol: Comparing Various Activating Modes, the Use of Bentonitic Clay as the Catalyst, and the Use of a Green Solvent

After attending both the “Decade to Educate in the Sustainable Development and the Agenda 30 of the UNESCO” and the “ACS GCI Pharmaceutical Roundtable”, which focused on sustainable chemistry, in this article, a green chemistry contribution to the Kamal Qureshi protocol is offered; thus, DIM® and several of its analogs (3,3′-diindolylmethanes) were suitably produced under the green chemistry protocol. In the first stage, the substrate indol-3-yl carbinol was evaluated using mechanochemistry (the best mode) in comparison to other activating methods (near-infrared and microwave electromagnetic irradiation and ultrasound), wishing to highlight the employment of both TAFF®, an excellent and well-characterized natural catalyst (bentonitic clay), and acetone, a green solvent, in addition to the analysis of the procedures in real-time. In the second stage, the mechanochemical methodology was extended to produce a set of fifteen DIMs, in the last stage, the use of a green metric exhibited the greenness of the approach, with it being important to highlight that, to our knowledge, after a search in the literature, this is the first time that the process has been evaluated to demonstrate its greenness.