Oxidation/reduction initiated domino

During the past few years, increasing numbers of reports have been published on the subject of domino reactions initiated by oxidation or reduction processes. This was in stark contrast to the period before our first comprehensive review of this topic was published in 1993 [1], when the use of this type of transformation was indeed rare. The benefits of employing oxidation or reduction processes in domino sequences are clear, as they offer easy access to reactive functionalities such as nucleophiles (e. g., alcohols and amines) or electrophiles (e. g., aldehydes or ketones), with their ability to participate in further reactions. For that reason, apart from combinations with photochemically induced, transition metal-catalyzed and enzymatically induced processes, all other possible constellations have been embedded in the concept of domino synthesis. 

Oxidation and reduction reactions play a vital role in the field of synthetic organic chemistry. Mild, selective, and economical catalytic oxidations as well as reduction reactions are recent developments in modern synthetic organic chemistry [1]. These transformations in combination with other reactions in a domino fashion give synthetically challenging organic products or intermediates in a very short and economical way [2]. After the first book by Tietze et al. [2a] in 2006 about domino reactions, where domino reactions initiated by oxidation or reduction reactions are reviewed as a separate chapter, enormous developments have taken place in the synthesis of a multitude of important organic compounds using oxidative or reductive domino reactions. 

Since oxidation and reduction reactions can provide many organic compounds with reactive functional groups such as aldehydes, ketones, enones, amines, alcohol, allylic alcohols, and so on, further transformations can easily be added to give a domino process. Depending upon the position of the oxidation or reduction reaction in the domino process, this chapter is divided into three classes first, the domino reaction is initiated by an oxidation or reduction reaction second, the domino reaction has the oxidation or reduction step in the middle and third, the domino reaction is terminated by an oxidation or reduction reaction. Most of the oxidation and reduction reactions come under the category of anionic domino process, as they provide nucleophilic or electrophihc functionalities and only very few oxidation and reduction reactions proceed with cationic domino process. 

Domino Reactions Initiated by Oxidation or Reduction Reaction... 

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