Related Experiment Video
Updated: Jun 16, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Practical Catalytic Asymmetric Synthesis of Gem-Dimethyl Bicyclic [3.1.0] Proline: A Valuable Building Block for
Yangyang Zhong1, Min Zhang1, Mingwei Li1
1Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
Abstract:
We report a practical catalytic asymmetric synthesis of gem-dimethyl bicyclic [3.1.0] proline, a valuable noncanonical amino acid scaffold widely found in antiviral protease inhibitors. The strategy features a catalytic enantioselective bromocyclization (95% ee) followed by a substrate-controlled, diastereoselective dibromocyclopropanation (trans only). This approach avoids both chiral resolution and cyanide-based transformations, delivering the target in 11% overall yield over nine steps. The concise and scalable nature of this route provides efficient access to this pharmaceutically relevant building block.
More Related Videos
06:34Synthesis of Antiviral Tetrahydrocarbazole Derivatives by Photochemical and Acid-catalyzed C-H Functionalization via Intermediate Peroxides (CHIPS)
Published on: June 20, 2014
11:04Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Related Concept Videos
Preparation of 1° Amines: Gabriel Synthesis
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
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.
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Prochirality
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.