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This work reports a cyanide‐free continuous‐flow process for cyanation of sp2 and sp carbons to synthesize aryl, vinyl and acetylenic nitriles from (5‐methyl‐2‐phenyloxazol‐4‐yl) boronic acid [OxBA] reagent as a sole source of carbon‐bound masked −CN source. Non‐toxic and stable OxBA reagent is generated by lithiation‐borylation of bromo‐oxazole, and the consecutive Suzuki‐Miyaura cross‐coupling with aryl, vinyl, or acetylenic halides and demasking [4+2]/retro‐[4+2] sequence were successfully accomplished to give the desired cyano compounds with reasonably good yields in a four‐step flow manner. A unique feature of this cyanation protocol in flow enables to cyanate a variety of sp2 and sp carbons to produce a broad spectrum of aryl acetonitrile. It is envisaged that the OxBA based cyanation would replace existing unstable and toxic approaches as well as non‐toxic cyanation using two different sources of "C" and "N" to incorporate the −CN group. [ABSTRACT FROM AUTHOR]

Output saturation is observed in many chemical processes and microbial cultivation processes. In these processes, output saturation can cause a number of control problems near the saturation point due to the nonlinear continuous input multiplicity interval after the saturation point. In general, the widely used proportional‐integral‐derivative (PID) controller cannot perform its function due to the nonlinearity. In particular, the accumulated error due to the integration term in the saturation region may result in a reduction in the energy efficiency and in an overloading of the process. Two solutions to this optimization problem are presented in this study. The first is to eliminate input multiplicity through a modified PID controller that introduces a new output value with the input signal added. The second is to find the optimal point of the nonlinear saturation process using extremum seeking control with continuous perturbation. Overflow experiments and simulations involving the liquid level system were performed for both solutions. Both methods have different characteristics, but both exhibit remarkable performance and stability improvements over conventional control systems. [ABSTRACT FROM AUTHOR]

This work reports a cyanide-free continuous-flow process for cyanation of sp 2 and sp carbons to synthesize aryl, vinyl and acetylenic nitriles from (5-methyl-2-phenyloxazol-4-yl) boronic acid [OxBA] reagent as a sole source of carbon-bound masked -CN source. Non-toxic and stable OxBA reagent is generated by lithiation-borylation of bromo-oxazole, and the consecutive Suzuki-Miyaura cross-coupling with aryl, vinyl, or acetylenic halides and demasking [4+2]/retro-[4+2] sequence were successfully accomplished to give the desired cyano compounds with reasonably good yields in a four-step flow manner. A unique feature of this cyanation protocol in flow enables to cyanate a variety of sp 2 and sp carbons to produce a broad spectrum of aryl acetonitrile. It is envisaged that the OxBA based cyanation would replace existing unstable and toxic approaches as well as non-toxic cyanation using two different sources of "C" and "N" to incorporate the -CN group., (© 2021 Wiley-VCH GmbH.)