Related Experiment Video
Updated: Jun 11, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Diastereoselective synthesis of spiro[2.n]alkanes via intramolecular carbolithiation
Charlotte S Teschers1,2, Cyriac Barra1, Maximilian Scherübl1
1Schulich Faculty of Chemistry, the Resnick Sustainability Center for Catalysis, Technion - Israel Institute of Technology Technion City Haifa 3200009 Israel chilanm@technion.ac.il charlotte.teschers@mpikg.mpg.de.
Abstract:
Spirocycles are appealing motifs for drug design owing to their inherently rigid three-dimensional structure, but synthetic strategies to construct highly substituted spiroalkanes remain scarce. We report a highly diastereoselective protocol for the synthesis of spiro[2.n]alkanes via intramolecular carbolithiation of cyclopropenes. The methodology provides straightforward access to spiro[2.n]alkanes as single diastereomers, with up to three contiguous quaternary centres. The trapping of a generated intermediate with an electrophile provides access to functionalized spirocycles bearing halo, silyl, alcohol or carbonyl functionalities.
Related Concept Videos
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Cycloaddition Reactions: Overview
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.
Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
