Recent Applications of Ritter Reactions in Organic Syntheses

Abstract

The Ritter reactions are an important Classes of organic reactions in the synthesis of heterocycles and linear amides. Ritter reaction products are pyridine, quinazolinone, and other heterocyclic structures, which have different biological activities such as antibacterial and antivirous application from 2017 to 2020. Furthermore, the Ritter reaction in the synthesis of linear amides is evaluated from 2015 to 2020 in this review. Linear amides are essential components in drug molecules which are difficult to synthesize by conventional methods but can be synthesized through the Ritter reaction.

Syntheses of Aristotelia Alkaloids: Reflections in the Chiral Pool

“…Although the Ritter-like reaction with monoterpenes has provided general, rapid access to the Aristotelia alkaloid scaffold, this approach is not without its shortcomings. [16][17][18] Both the mercury-and Brønsted acid mediated reactions typically employ a large excess of the nitrile, which may not always be economically or synthetically feasible. Also, as highlighted in Scheme 3, terpenes are notoriously prone to acid-catalyzed rearrangements giving rise to various isomeric byproducts.…”

Discovery of New Ginsenol-Like Compounds with High Antiviral Activity

“…Among the widely known methods, the Ritter reaction, a method for the synthesis of N-substituted amides of carboxylic acids by alkylation of nitriles with carbocations, occupies a special position [38]. Under acid catalysis, alkenes or their derivatives, alcohols, oxiranes, etc., can act as carbocation precursors [39]. This reaction has attracted the attention of researchers due to the simplicity and availability of the reagents used, and the class of catalysts used in this reaction has recently been significantly expanded [40].…”

Visible-light-mediated aerobic Ritter-type C–H amination of diarylmethanes using DDQ/tert-butyl nitrite

“…Catalytic transformation of omnipresent C–H bonds to C–N bonds offers an efficient synthetic strategy for the construction of valuable nitrogen-containing compounds. 1–3 As one of the most popular strategies to construct C–N bonds, the Ritter reaction has been established as a powerful tool for the synthesis of amides, 4–6 which widely exist in modern pharmaceutical molecules. 7,8 The classic Ritter reaction involves the generation of a carbocation from a functionalized substrate ( e.g.…”

“…1A). 4–6 Recently, much effort has been directed towards the development of catalytic Ritter-type C–H amination, which allows amides to be selectively synthesised from non-functionalized alkanes, with the carbocation intermediate generated from C–H bond oxidation using a variety of oxidants such as ceric ammonium nitrate (CAN), 9 Selectfluor, 10 hypervalent iodine, 11 iodic acid, 12 3-dichloro-4,5-dicyano-1,4-benzoquinone (DDQ) 13 and sodium persulfate 14 (Fig. 1B).…”