3 years ago

Asymmetric Michael addition reaction organocatalyzed by stereoisomeric pyrrolidine sulfinamides under neat conditions. A brief study of self-disproportionation of enantiomers

Asymmetric Michael addition reaction organocatalyzed by stereoisomeric pyrrolidine sulfinamides under neat conditions. A brief study of self-disproportionation of enantiomers
This paper describes the synthesis of all four possible stereoisomers of the pyrrolidine sulfinamides derived from (S)-proline or (R)-proline and either enantiomer of t-butylsulfinamide. These bifunctional derivatives were examined as organocatalysts in the asymmetric Michael addition reaction, finding that the pyrrolidine stereocenter, rather than the stereogenic sulfur, is responsible for the observed stereocontrol in the asymmetric reaction. This result is in accordance with previous reports in the literature (aldol reactions: W. Wan, J. Hao, and coworkers, RSC Adv. 2014, 4, 26563–26568; J. A. Ellman et al., Tetrahedron 2011, 67, 4412–4416). Consequently, no evidence for double stereoinduction is found. The desired Michael adducts were obtained with good yields, high diastereoselectivities, and moderate to good enantioselectivities. Some tests designed to examine the potential manifestation of self-disproportionation of enantiomers (SDE) were carried out by means of chromatographic purification and subsequent evaluation of the enantiopurity of the corresponding Michael adducts.

Publisher URL: www.sciencedirect.com/science

DOI: S0040402017304829

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.