Related Experiment Video
Updated: Jun 4, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Lewis-Acid-Catalyzed Cyclization of Bicyclo[1.1.0]butanes with Alkenyl Cyclic Dithioacetals for the Synthesis of
Hua Chen1,2, Junmin Zhang1, Lihang Cao1
1College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China.
Abstract:
Medium-sized rings are valuable synthetic scaffolds yet challenging to construct. Herein, we report a Lewis-acid-catalyzed (8 + 3) cycloaddition of bicyclo[1.1.0]butanes with alkenyl cyclic dithioacetals that provides efficient access to previously inaccessible 11-membered bicyclo[8.1.1] skeletons. Driven by strain release and catalyzed by Lu(OTf)3, this ring expansion proceeds under mild conditions, exhibits a broad substrate scope, and delivers products in excellent yields (46 examples, with yields up to 94%). Mechanistic studies and DFT calculations support a pathway involving sequential nucleophilic attack, ring opening, and regioselective intramolecular 1,4-addition.
More Related Videos
11:45Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
10:17Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Related Concept Videos
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.
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
Cycloaddition Reactions: Overview
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation