New One-Pot Methods for Preparation of Cyclohexanecarbonitrile—Green Chemistry Metrics Evaluation for One-Pot and Similar Multi-Step Syntheses

Abstract

Three new multi-step one-pot processes for high-yielding cyclohexanecarbonitrile synthesis starting from cyclohexanone were developed for industrial application. In contrast to the current synthetic process, all of the processes described were designed to proceed completely in methanol as a uniform solvent and the key oxidation step can be realized either as stoichiometric or catalytic. Atom efficiency of processes is relatively advanced with high regioselectivity, reaction by-products are either from environmental pool-carbon dioxide and nitrogen-or they can be reusedsodium chloride. Solvent-methanol-and other auxiliaries-cyclohexane, copper catalyst-can be reused after recycling as well. EcoScale for all three designed processes was evaluated and compared with current synthesis described in the past. Green chemistry metrics, including newly introduced evaluative tool-Sustainability Index of the Synthesis (SIS), were applied to evaluate design of described one-pot syntheses.

Mass Efficiency of Alkene Syntheses with Tri- and Tetrasubstituted Double Bonds

“…Further examples for the utilization of mass metrics (and approaches to consider health, safety, and environment aspects) can be found not only in the professional literature (e.g., bromination reactions, ,, photochemical transformations, ,, methylating agents, , cross-metathesis, , esterifications, , substitution reactions, , reduction reactions, ,, oxidation reactions, , asymmetric ,,, /biocatalytic , syntheses, azidation, deprotection, total synthesis, flash chromatography as method and other ,,− ) but also in chemical didactics. ,− Further references − …”

Green Chemistry Metrics with Special Reference to Green Analytical Chemistry

“…Information needed for performing EATOS analysis can easily be found in the substance specification sheets. More details about this tool and examples of its use have been presented by many authors [52,53,54,55].…”

The EcoScale as a framework for undergraduate green chemistry teaching and assessment

“…A major strength of this approach is that it allows the direct comparison of different routes towards the same target compound. The EcoScale has found favor as an assessment tool in academic laboratories (13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25) and has been modified for industrial purposes (26). It has also been incorporated into some undergraduate pedagogical laboratory exercises (9,27), although it has not, to our knowledge, been utilized as a formal way to evaluate student learning and understanding of green chemistry.…”