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Updated: Jul 9, 2026
07:36
Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy
Published on: November 9, 2019
Acyclic 1,4-stereocontrol via reductive 1,3-transpositions
1119 Chemistry Building, University of Arkansas, Fayetteville, Arkansas 72701, USA.
Organic Letters
|December 21, 2007
Summary
This study introduces a one-pot method for synthesizing E-2-alkenyl arrays with high diastereoselectivity. Researchers can control the formation of syn or anti diastereomers by selecting specific alkene stereoisomers of tosyl hydrazones.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Tosyl hydrazones are versatile synthetic intermediates.
- Stereoselective synthesis of complex organic molecules remains a key challenge.
Purpose of the Study:
- To develop a novel one-pot method for synthesizing E-2-alkenyl arrays.
- To achieve high diastereoselectivity in the formation of 1,4-syn and 1,4-anti isomers.
Main Methods:
- One-pot reduction and allylic diazene rearrangement of alpha,beta-unsaturated tosyl hydrazones.
- Utilizing lactic acid- and mandelic acid-derived precursors.
- Employing specific alkene stereoisomers (E or Z) of the hydrazone.
Main Results:
- High yields and diastereoselectivity (> or =20:1) for 1,4-syn and 1,4-anti E-2-alkenyl arrays.
- E-alkenes of hydrazones selectively yield 1,4-syn isomers.
- Z-alkenes of hydrazones selectively yield 1,4-anti isomers.
Conclusions:
- The developed method offers a stereocontrolled approach to E-2-alkenyl arrays.
- Alkene geometry in tosyl hydrazones dictates the diastereoselectivity of the product.
- This strategy provides access to both syn and anti diastereomers with high precision.
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