The Ritter Reaction: Trapping a Carbocation with a Nitrile

Abstract

the microscale laboratory Figure 2. Standard curve for Cu2+ analysis using a microwell colorimeter. Food DyePortions ofblue food dye (6, 5,4,3, 2,1, and 0 drops) are placed into different wells and diluted to a volume of six drops by adding water. The resistance of each is measured and a plot of resistance versus volume of dye (drops) is generated.

Route Evaluation and Ritter Reaction Based Synthesis of Oxazoline Acaricide Candidates FET-II-L and NK-12

“…Finally, we explored the aminohalogenation of 4-chloromethylstyrene by means of a Ritter reaction with 2,6-difluorobenzonitrile ( 22 ) as the nitrogen source (Scheme , route 4; Table ). Though the Ritter reaction of nitriles on carbenium ion (or its chemical equivalent) is known, the substrate scopes are limited. − Screening of various halogen sources at room temperature revealed NBS to be the best choice. Dichloromethane was a better solvent than chloroform, and sulfuric acid was a better catalyst than AlCl 3 (entries 1–3).…”

“…According to refs , , and − , the mechanism for this transformation is depicted in Scheme . First, reaction of 4-chloromethylstyrene and NBS gives bromonium ion 24 , which is readily transformed to benzyl cation 25 .…”

The Mechanism of the Ritter Reaction in Combination with Wagner-Meerwein Rearrangements. A Cooperative Learning Experience

“…Three publications in this Journal have highlighted the use of the Ritter reaction as an instructional laboratory (8)(9)(10). Hathaway ( 8) described an open-ended investigation for students to examine a possible mechanism for the reaction of an acetic acid solution of benzonitrile and tert-butyl alcohol in the presence of concentrated sulfuric acid (Scheme I).…”

“…Crouch described a discovery-based exercise using the same Ritter reaction under slightly different reaction conditions to demonstrate the trapping of a carbocation intermediate by a nitrile, which produces an amide by aqueous hydrolysis (9). Crouch notes that while the formation of a 3° carbocation is easily recognized by students, the benzamide product is not usually predicted, and this is precisely why this type of experiment helps students to develop analytical and problem-solving skills.…”

The serendipitous effect of KF in Ritter reaction: Photo-induced amino-alkylation of alkenes

“…Since its discovery in 1948 ( Ritter and Kalish, 1948 ; Ritter and Minieri, 1948 ), Ritter reaction has been recognized as one of the most powerful methods for amide synthesis through the formation of the C−N bond ( Scheme 1 A) ( Bolsakova and Jirgensons, 2017 ; Crouch, 1994 ; Guérinot et al., 2012 ; Jiang et al., 2014 ; Kürti and Czakó, 2005 ; Li-Zhulanov et al., 2020 ; Mohammadi Ziarani et al., 2020 ; Pronin et al., 2013 ; Qu et al., 2012 ; Zheng et al., 2015 ). This two-component protocol usually involves the generation of carbocation intermediates from tertiary, secondary, and benzylic alcohols under acidic conditions ( Kürti and Czakó, 2005 ).…”