Stereocontrolled formation of tertiary or quaternary chiral carbons bearing nitrogen was achieved using the [3,3]-sigmatropic rearrangement of cyanate to isocyanate as a key element. A short and highly selective sequence of reactions, starting from p-menthane-3-carboxaldehyde, was developed leading to alpha,alpha-dialkylated alpha-amino acids or N-heterocycles, depending on the method of cleavage of the auxiliary.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/ol053061g | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Enantiocontrolled Cyclization to Form Chiral 7- and 8-Membered Rings Unified by the Same Catalyst Operating with Different Mechanisms.
J Am Chem Soc
January 2025
Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.
Chiral medium-sized rings, albeit displaying attractive properties for drug development, suffer from numerous synthetic challenges due to difficult cyclization steps that must take place to form these unusually strained, atropisomeric rings from sterically crowded precursors. In fact, catalytic enantioselective cyclization methods for the formation of chiral seven-membered rings are unknown, and the corresponding eight-membered variants are also sparse. In this work, we present a substrate preorganization-based, enantioselective, organocatalytic strategy to construct seven- and eight-membered rings featuring chirality that is intrinsic to the ring in the absence of singular stereogenic atoms or single bond axes of chirality.
View Article and Find Full Text PDFStereocontrolled Synthesis of the Portimine Skeleton via Organocatalyst-Mediated Asymmetric Stannylation and Stereoretentive C()-C() Stille Coupling.
Org Lett
January 2025
Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, 980-8577 Aoba-ku, Sendai, Japan.
Our efforts toward the synthesis of the marine natural product portimine are described. The key to the synthesis of the skeleton is a stereoretentive copper-catalyzed C()-C() Stille-type cross-coupling that enables the convergent assembly of functionalized fragments. The core skeleton of portimine was constructed via ring-closing metathesis and transannular acetal formation.
View Article and Find Full Text PDFReactivity of Anomalous Aziridines for Versatile Access to High Fsp Amine Chemical Space.
Acc Chem Res
January 2025
Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, Wisconsin 53706, United States.
ConspectusThe manipulation of strained rings is a powerful strategy for accessing the valuable chemical frameworks present in natural products and active pharmaceutical ingredients. Aziridines, the smallest N-containing heterocycles, have long served as building blocks for constructing more complex amine-containing scaffolds. Traditionally, the reactivity of typical aziridines has been focused on ring-opening by nucleophiles or the formation of 1,3-dipoles.
View Article and Find Full Text PDFA Regio- and Stereoselective Ring-Opening Polymerization Approach to Isotactic Alternating Poly(lactic-co-glycolic acid) with Stereocomplexation.
Angew Chem Int Ed Engl
January 2025
Sichuan University - Wangjiang Campus: Sichuan University, Chemistry, 29 Wangjiang Rd, 610064, Chengdu, CHINA.
Poly(lactic-co-glycolic acid) (PLGA) has been widely employed for various biomedical applications owing to its biodegradability and biocompatibility. The discovery of the stereocomplex formation between enantiomeric alternating PLGA pairs underscored its potential as high-performance biodegradable materials with diverse material properties and biodegradability. Herein, we have established a regio- and stereoselective ring-opening polymerization approach for the synthesis of stereocomplexed isoenriched alternating PLGA from racemic methyl-glycolide (rac-MG).
View Article and Find Full Text PDFEngineered enzymes for enantioselective nucleophilic aromatic substitutions.
Nature
January 2025
Manchester Institute of Biotechnology, The University of Manchester, Manchester, UK.
Nucleophilic aromatic substitutions (SAr) are amongst the most widely used processes in the pharmaceutical and agrochemical industries, allowing convergent assembly of complex molecules through C-C and C-X (X = O, N, S) bond formation. SAr reactions are typically carried out using forcing conditions, involving polar aprotic solvents, stoichiometric bases and elevated temperatures, which do not allow for control over reaction selectivity. Despite the importance of SAr chemistry, there are only a handful of selective catalytic methods reported that rely on small organic hydrogen-bonding or phase-transfer catalysts.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!