β-Amino functionalization of cinnamic Weinreb amides in ionic liquid
Beilstein Institut -- Beilstein Journal of Organic Chemistry
DOI 10.3762/bjoc.12.231
Keyword(s)
  1. aminochlorination
  2. β-amino functionalization
  3. ionic liquid
  4. Weinreb amides
Abstract(s)

2-Ns-Protected β-amino Weinreb amides were synthesized by aminochlorination of α,β-unsaturated Weinreb amides in an ionic liquid, 1-n-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([BMIM][NTf2]). Processed without the use of metal catalysts or the need of an inert gas atmosphere, the presented process can be readily performed as a one-pot synthesis at room temperature. Moreover, the preparation has the distinct advantages of the use of 2-NsNCl2 as an inexpensive and stable nitrogen/halogen source and the ionic liquid as a recyclable reaction media. Nine examples were examined, and modest to good isolated chemical yields (40–83%) were obtained.