Pyrimidyl alkanol was found to act as an asymmetric autocatalyst in the enantioselective addition of diisopropylzinc to pyrimidine-5-carbaldehyde. Asymmetric autocatalysis of 2-alkynylpyrimidyl alkanol with an extremely low enantiomeric excess (ca. 0.00005% ee) exhibits enormous asymmetric amplification to afford the same compound with >99.5% ee. This asymmetric autocatalysis with amplification of ee has been employed to examine the validity of proposed theories of the origins of homochirality. Circularly polarized light, quartz, sodium chlorate, cinnabar, chiral organic crystals and spontaneous absolute asymmetric synthesis were considered as possible candidates for the origin of chirality; each could act as a chiral source in asymmetric autocatalysis. Asymmetric autocatalysis can discriminate the isotope chirality arising from the small difference between carbon (carbon-13/carbon-12) and hydrogen (D/H) isotopes. Cryptochiral compounds were also discriminated by asymmetric autocatalysis.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/tcr.201300028 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Anion-π catalysis on carbon allotropes.
Beilstein J Org Chem
December 2023
Department of Organic Chemistry, University of Geneva, Geneva, Switzerland.
Anion-π catalysis, introduced in 2013, stands for the stabilization of anionic transition states on π-acidic aromatic surfaces. Anion-π catalysis on carbon allotropes is particularly attractive because high polarizability promises access to really strong anion-π interactions. With these expectations, anion-π catalysis on fullerenes has been introduced in 2017, followed by carbon nanotubes in 2019.
View Article and Find Full Text PDFThe Reduction of Carbonyl Compounds with Dicyclopentylzinc: A New Example of Asymmetric Amplifying Autocatalysis.
Int J Mol Sci
December 2023
N. D. Zelinsky Institute of Organic Chemistry, Leninsky Prosp. 47, 119991 Moscow, Russia.
A previously unknown reduction of carbonyl compounds with dicyclopentylzinc is reported. Aldehydes react in mild conditions yielding corresponding primary alcohols and cyclopentene. Although cyclohexanone and acetophenone are inert to dicyclopentylzinc, a variety of heterocyclic ketones reacted readily, yielding reasonable to high yields of corresponding secondary alcohols.
View Article and Find Full Text PDFAchiral 2-pyridone and 4-aminopyridine act as chiral inducers of asymmetric autocatalysis with amplification of enantiomeric excess via the formation of chiral crystals.
Chirality
January 2024
Department of Applied Chemistry, Tokyo University of Science, Tokyo, Japan.
Article Synopsis
- - Achiral 2-pyridone and 4-aminopyridine crystals acted as sources of chirality in a reaction involving 5-pyrimidyl alkanol, promoting asymmetric autocatalysis known as the Soai reaction.
- - During this process, diisopropylzinc was added to pyrimidine-5-carbaldehyde, leading to the creation of enantioenriched products.
- - The reaction resulted in a significant increase in enantiomeric excess, with the final 5-pyrimidyl alkanol mirroring the configurations of the original chiral crystals.
Autocatalytic Mechanism in the Anaerobic Reduction of Metmyoglobin by Sulfide Species.
Inorg Chem
July 2023
Instituto de Química Física de Los Materiales, Medio Ambiente y Energía (INQUIMAE), CONICET-Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina.
The mechanism of the metal centered reduction of metmyoglobin (MbFe) by sulfide species (HS/HS) under an argon atmosphere has been studied by a combination of spectroscopic, kinetic, and computational methods. Asymmetric S-shaped time-traces for the formation of MbFe at varying ratios of excess sulfide were observed at pH 5.3 < pH < 8.
View Article and Find Full Text PDFThe Origin of Anion-π Autocatalysis.
JACS Au
April 2023
Department of Organic Chemistry, University of Geneva, CH-1211 Geneva, Switzerland.
The autocatalysis of epoxide-opening ether cyclizations on the aromatic surface of anion-π catalysts stands out as a leading example of emergent properties expected from the integration of unorthodox interactions into catalysis. A working hypothesis was proposed early on, but the mechanism of anion-π autocatalysis has never been elucidated. Here, we show that anion-π autocatalysis is almost independent of peripheral crowding in substrate and product.
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!