scholarly journals Direct Access to Highly Enantioenriched α-Branched Acrylonitriles through a one-pot Sequential Asymmetric Michael addition/retro-Dieckmann/retro-Michael Fragmentation Cascade

2020 ◽  
Author(s):  
Nicolas Duchemin ◽  
Martin Cattoen ◽  
Oscar Gayraud ◽  
Silvia Anselmi ◽  
Bilal Siddiq ◽  
...  
Keyword(s):  
Michael Addition ◽  
Building Blocks ◽  
Enantioselective Synthesis ◽  
Direct Access ◽  
One Pot ◽  
Asymmetric Michael Addition ◽  
Wide Range

A highly enantioselective synthesis of a-branched acrylonitriles is reported featuring a one-pot sequential asymmetric Michael addition/retro-Dieckmann/retro-Michael fragmentation cascade. The method, which relies on a solid, bench-stable and commercially available acrylonitrile surrogate, is practical, scalable, highly versatile, and provides a direct access to a wide range of enantioenriched nitrile-containing building blocks. Most importantly, the method offers a new tool to incorporate an acrylonitrile moiety in an asymmetric fashion.<br>

scholarly journals Direct Access to Highly Enantioenriched α-Branched Acrylonitriles through a Formal Cross Rauhut-Currier Reaction

2020 ◽  
Author(s):  
Nicolas Duchemin ◽  
Martin Cattoen ◽  
Oscar Gayraud ◽  
Silvia Anselmi ◽  
Bilal Siddiq ◽  
...  
Keyword(s):  
Michael Addition ◽  
Building Blocks ◽  
Enantioselective Synthesis ◽  
Direct Access ◽  
Asymmetric Michael Addition ◽  
Wide Range

A highly enantioselective synthesis of α-branched acrylonitriles is reported featuring an unprecedented formal cross Rauhut-Currier reaction consisting of an asymmetric Michael addition/retro-Dieckmann/retro-Michael fragmentation cascade. The method, which involves the use of an acrylonitrile surrogate, is practical, scalable and highly versatile, and provides a straightforward access to a wide range of enantioenriched nitrile-containing building blocks without using acrylonitrile or any source of cyanide. Most importantly, it offers a new tool to incorporate an acrylonitrile moiety in an asymmetric fashion.<br>

scholarly journals Direct Access to Highly Enantioenriched α-Branched Acrylonitriles through a One-Pot Sequential Asymmetric Michael Addition/Retro-Dieckmann/Retro-Michael Fragmentation Cascade

2020 ◽  
Vol 22 (15) ◽  
pp. 5995-6000 ◽  
Author(s):  
Nicolas Duchemin ◽  
Martin Cattoen ◽  
Oscar Gayraud ◽  
Silvia Anselmi ◽  
Bilal Siddiq ◽  
...  
Keyword(s):  
Michael Addition ◽  
Direct Access ◽  
One Pot ◽  
Asymmetric Michael Addition

ChemInform Abstract: Highly Enantioselective Synthesis of α-Fluoro-α-nitro Esters via Organocatalyzed Asymmetric Michael Addition.

ChemInform ◽  
2011 ◽  
Vol 42 (16) ◽  
pp. no-no
Author(s):  
Hai-Feng Cui ◽  
Peng Li ◽  
Xiao-Wei Wang ◽  
Zhuo Chai ◽  
Ying-Quan Yang ◽  
...  
Keyword(s):  
Michael Addition ◽  
Enantioselective Synthesis ◽  
Asymmetric Michael Addition ◽  
Nitro Esters

scholarly journals Thioesters Provide a Robust Path to Prebiotic Peptides

2021 ◽  
Author(s):  
Moran Frenkel-Pinter ◽  
Marcos Bouza ◽  
Facundo M. Fernández ◽  
Luke J. Leman ◽  
Loren Dean Williams ◽  
...  
Keyword(s):  
Building Blocks ◽  
Peptide Bond ◽  
Side Reactions ◽  
Peptide Bond Formation ◽  
One Pot ◽  
Complex Molecules ◽  
Peptide Formation ◽  
Wide Range ◽  
Amide Exchange ◽  
Prebiotic Earth

The condensation of building blocks into oligomers and polymers was an early and important stage in the origins of life. High activation energies, unfavorable thermodynamics and side reactions are bottlenecks for abiotic formation of peptides. Thioesters are hypothesized to have played key roles in prebiotic chemistry on early Earth, serving as energy storing molecules, as synthetic intermediates, and as catalysts in the formation of more complex molecules, including polypeptides. However, all abiotic reactions reported thus far for peptide formation via thioester intermediates have relied on activated building blocks or condensing agents, which are of questionable prebiotic relevance. We report robust, plausible prebiotic reactions of mercaptoacids with amino acids that result in the formation of peptides and thiodepsipeptides, which contain both peptide and thioester bonds. Peptide bond formation proceeds by the condensation of mercaptoacids to form thioesters followed by thioester-amide exchange. Mercaptoacids catalyze thiodepsipeptides and peptide formation under a wide range of pH conditions and at mild temperatures. Our results offer the most robust one-pot pathway for peptide formation ever reported. These results support the hypothesis that thiodepsipeptides formed robustly on prebiotic Earth and were possible contributors to early chemical evolution.

scholarly journals A novel three-component reaction between isocyanides, alcohols or thiols and elemental sulfur: a mild, catalyst-free approach towards O-thiocarbamates and dithiocarbamates

2019 ◽  
Vol 15 ◽  
pp. 1523-1533 ◽  
Author(s):  
András György Németh ◽  
György Miklós Keserű ◽  
Péter Ábrányi-Balogh
Keyword(s):  
Elemental Sulfur ◽  
Building Blocks ◽  
Reaction Conditions ◽  
One Pot ◽  
Catalyst Free ◽  
Synthetic Procedure ◽  
Three Component Reaction ◽  
Wide Range ◽  
Organic Chemist ◽  
The One

A new multicomponent reaction has been developed between isocyanides, sulfur and alcohols or thiols under mild reaction conditions to afford O-thiocarbamates and dithiocarbamates in moderate to good yields. The one-pot reaction cascade involves the formation of an isothiocyanate intermediate, thus a catalyst-free synthesis of isothiocyanates, as valuable building blocks from isocyanides and sulfur is proposed, as well. The synthetic procedure suits the demand of a modern organic chemist, as it tolerates a wide range of functional groups, it is atom economic and easily scalable.

Sign in / Sign up

Export Citation Format

Share Document