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High throughput experimentation is a growing and evolving field that allows to execute dozens to several thousands of experiments per day with relatively limited resources. Through miniaturization, typically a high degree of automation and the use of digital data tools, many parallel reactions or experiments at a time can be run in such workflows. High throughput experimentation also requires fast analytical techniques capable of generating critically important analytical data in line with the increased rate of experimentation. As traditional techniques usually do not deliver the speed required, some unique approaches are required to enable workflows to function as designed. This review covers the recent developments (2019‐2020) in this field and was intended to give a comprehensive overview of the current "state‐of‐the‐art." [ABSTRACT FROM AUTHOR]

The potential of halogen-magnesium exchange reactions, followed by quenching with electrophiles was explored for the functionalization of the pyridazin-3(2H)-one core. A tandem reaction involving nucleophilic substitution via addition elimination and bromine-magnesium exchange was observed with 2-benzyl-5-bromo-4-methoxy while 2-b enzyl-4-bromo-5-methoxy and 2-benzyl-4,5-dibromopyridazin-3(2H)-one gave exclusively C-4 metalation.

The use of amidines for the tandem or one-pot synthesis of guanidines is reported. Guanidines are obtained by oxidative rearrangement of readily available and stable amidines into carbodiimides, followed by in situ reaction with amines. The protocol can be executed under mild reaction conditions (30 °C), in a green solvent (dimethyl carbonate). The amine scope is broad, including sterically hindered, oxidation-sensitive and chiral amines. Examples for the synthesis of both acyclic and cyclic guanidines are provided. 2-Propoxyphenyl iodide (2-PrOPhI) by-product, generated from the oxidant [ N-( p-toluenesulfonyl)imino](2-propoxyphenyl)iodinane (2-PrOPhINTs), can be isolated in high yields making regeneration of the hypervalent iodine reagent possible. The utility and greenness of the synthetic method versus the state-of-the-art is demonstrated by a new route towards the antihypertensive drug Pinacidil. The process mass intensity (PMI) of the new route is only 24% of the classical one. [ABSTRACT FROM AUTHOR]

In this work an efficient tandem process transforming N-substituted amidines into secondary amides has been described. The process involves N-acylurea formation by reaction of the substrate with bis(acyloxy)(phenyl)-λ3-iodane followed by isocyanate elimination. The periodinane reagents are obtained from the commercially available phenyliodine(III) diacetate [PhI(OAc)2, (PIDA)] by ligand exchange with carboxylic acids. The N-substituted amidine substrates are easily synthesized from readily available nitriles. The method is applicable for secondary amide synthesis, based on both aliphatic and (hetero)aromatic amines, including challenging amides consisting of sterically hindered acids and amines. Moreover, the protocol allows one to combine steric bulk with electron deficiency in the target amides (aniline based). Such compounds are difficult to synthesize efficiently based on classical condensation reactions involving carboxylic acids and amines. Overall, the synthetic protocol transforms a nitrile into a secondary amide in both aliphatic and (hetero)aromatic systems. [ABSTRACT FROM AUTHOR]

A general method for transformation of readily available, stable amidine substrates into substituted guanidines is developed. [ABSTRACT FROM AUTHOR]

This new, efficient tandem process for the transformation of N-substituted amidines into secondary amides is applicable for aliphatic and (hetero)aromatic compounds. [ABSTRACT FROM AUTHOR]