Related Experiment Video
Updated: Mar 21, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Lewis Acid-Catalyzed Switchable Functionalization of C,N-Cyclic Ketimines with Vinyl Azides: Access to Diverse
Ashitosh Baruah1,2, Mainee Baruah1, Rassel M Bulbul1
1CSTD, CSIR-North East Institute of Science & Technology, Jorhat, Assam 785006, India.
Abstract:
Herein, a divergent coupling of indole-derived C,N-cyclic ketimines with vinyl azides is described for the synthesis of structurally diverse C(2)-alkylated pseudoindoxyls, especially α-indoxylacetamides, ketones, and acetonitrile derivatives. The Lewis acid-catalyzed divergent Schmidt and interrupted Schmidt-type pathways of the transient iminodiazonium ion intermediate enable vinyl azides to effectively function as surrogates for amides, ketones, and cyanomethanides. Furthermore, α-indoxylacetamides exhibited fluorescence properties, demonstrating an impressive fluorescence quantum yield.
More Related Videos
Related Concept Videos
Preparation of 1° Amines: Azide Synthesis
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
α-Alkylation of Ketones via Enolate Ions
Amines to Amides: Acylation of Amines
Next, the second equivalent of amine serves as a Brønsted base and deprotonates the quaternary...
Acid-Catalyzed α-Halogenation of Aldehydes and Ketones
In the first step of the mechanism, the acid protonates the carbonyl oxygen resulting in a resonance-stabilized cation, which subsequently loses an α-hydrogen to form an enol tautomer. The C=C bond in an enol is highly nucleophilic because of the electron-donating nature of the –OH group. Consequently, the double bond attacks an electrophilic halogen to form a...
Carboxylic Acids to Methylesters: Alkylation using Diazomethane
Preparation of Alkynes: Alkylation Reaction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.

