10.1002/chem.201702616
Chemistry - A European Journal
FULL PAPER
The entire experimental section can be found in the supporting
information, including compound characterization data and copies of
NMR spectra.
Keywords: Pyrrolidine • Chiral auxiliary • Tsuji-Trost allylation.
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Scheme 9. Suzuki-Miyaura cross-coupling of 5l with pinacolboronate esters
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Conclusions
The synthesis of novel pyrrolidine containing chemical scaffolds
using chiral N-tert-butanesulfinyl imines has been investigated.
The Tsuji-Trost reaction was used to obtain α-allyl N-tert-
butanesulfinyl imines, followed by cross metathesis reaction to
give α,β-unsaturated esters. DIBAL-H was found to be
seteroselective reducing agent of the sulfinyl imine group of α,β-
unsaturated esters to afford the corresponding sulfinamides in
high d.r. in most cases (up to >25:1) in moderate to good yields
ranging from 58 to 86%. The sulfinamides were then used to
synthesise a range of pyrrolidine scaffolds via cyclisation in the
presence of NaH. The desired pyrrolidine products were isolated
in yields between 53% and 77% with d.r. up to >25:1. A range of
further derivatisation such as, sulfonylation, reductive amination,
amidation and Suzuki coupling leading to highly functionalised
substrates has been achieved successfully.
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[20] The ee value of 6 was determined by chiral GC-Lipodex E column. For
more details, see the supporting information.
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Acknowledgment
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Org. Chem. 2006, 71, 6859-6862.
We would like to thank the University of Nottingham and Ministry
of Higher Education and Scientific Research-Iraq (MOHESR) for
funding support.
Conflict of interest
The authors declare no conflict of interest.
Experimental Section
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