Synthesis of Chiral Acetals by Asymmetric Selenenylations

Asymmetric selenenylations of (E)-ethoxystyrene are described leading to chiral acetals. An efficient synthesis of such compounds including the determination of their absolute configuration is described

Mixed acetals as new precursors for selenium electrophiles

A wide range of precursors for selenium electrophiles is already known, but the requirements for the development of polymer-bound selenium reagents are different. Herein we report mixed acetals as new precursor molecules for the synthesis of selenium electophiles under very mild reaction conditions. The use of (MeOCH2Se)2 allows a very fast access to these mixed acetals. Chiral precursor molecules can be synthesized as well and employed in efficient stereoselective selenenylation reactions

Novel polymer-bound chiral selenium electrophiles

Polymer-bound chiral electrophilic selenium reagents have been developed and applied to stereoselective selenenylation reactions of various alkenes. Different cleavage protocols allow further functionalization of the addition products leading to improvements in selenium-based solid-phase chemistry

Chiral Selenium Electrophiles on Solid-Support

Organoselenium chemistry has developed rapidly and selenium-based methods are now very useful in synthetic chemistry. The selective introduction of various functionalities into complex molecules can be accomplished under very mild reaction conditions. This has led to versatile and new synthetic methods in organic chemistry. We have developed new and highly efficient selenium electrophiles and describe first attempts to use these reagents on polymer-support

Chiral selenium electrophiles on solid-support

Organoselenium chemistry has developed rapidly and selenium-based methods are now very useful in synthetic chemistry. The selective introduction of various functionalities into complex molecules can be accomplished under very mild reaction conditions. This has led to versatile and new synthetic methods in organic chemistry. We have developed new and highly efficient selenium electrophiles and describe first attempts to use these reagents on polymer-support

New and Efficient Chiral Selenium Electrophiles

New chiral diselenides were prepared in a few steps from readily available starting materials. The selenium electrophiles generated from these diselenides were used for the efficient stereoselective inter- and intramolecular functionalization of alkenes. The substitution pattern influences the stereoselectivities and protection of the hydroxy moiety in the chiral side chain led to increased selectivities and yields in the selenenylation reactions. An additional substituent in the second ortho position was advantageous as well. Addition products with up to 96 % de were obtained. The influence of the nucleophile on the outcome of selenenylations of alkenes was studied to some extent as well