Related Experiment Video
Updated: May 15, 2025

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Gold-Catalyzed Alkyne-Amine Cascade Annulations: A Modern Strategy for Azaheterocycle Construction
1Saint Petersburg State University, Universitetskaya Nab. 7/9, 199034, Saint Petersburg, Russian Federation.
Abstract:
Gold catalysis has experienced remarkable progress over the past two decades, particularly in transformations involving alkynes. While numerous aspects of gold-catalyzed reactions have been extensively reviewed, the specific area of cascade annulations between functionalized amines and alkynes represents a distinct and rapidly developing direction that warrants focused attention. This survey collects and systematically analyzes these transformations, which have emerged as convenient synthetic strategies to diverse nitrogen heterocycles. The relevant annulations are classified firstly by the chemical nature of the amine functional substituent, and secondly by the size of the formed ring. The field under consideration bridges several fundamental and practical branches of chemistry, including catalysis, organic synthesis, medicinal chemistry, and materials science.
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...
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview
Cycloaddition Reactions: Overview
Preparation of Alkynes: Dehydrohalogenation
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.
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.

