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?-Amino functionalization of cinnamic Weinreb amides in ionic liquid.

ABSTRACT: 2-Ns-Protected ?-amino Weinreb amides were synthesized by aminochlorination of ?,?-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.

SUBMITTER: Wang YN

PROVIDER: S-EPMC5238596 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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β-Amino functionalization of cinnamic Weinreb amides in ionic liquid.

Wang Yi-Ning YN Sun Guo-Xiang GX Qi Gang G

Beilstein journal of organic chemistry 20161111

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 i ...[more]

PMID: 28144305

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